RTU7 3V3I protection manual ver. 112.01 2013-01-21.pdf
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Transcript of RTU7 3V3I protection manual ver. 112.01 2013-01-21.pdf
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Protections and Automatics 3V3I
RTU7
Protections and Automatics Manual
Configuration 3V3I
Version of the parameters 112.01
Version of the records parameters 112.01
FW 112.01 or greater
Document version 2013-01-21
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Protections and Automatics 3V3I
Contents
CONTENTS 2
INTRODUCTION 4
MEASUREMENT 5
Sampling 5
Angles 5
Filtration 5 Frequency Measurement 5
Transmitting Measured Values 5
Ranges 6
Powers Measurement 6
Circuit Breaker Control 6
Group Switching 6
Initialization 6
Signalling 6
Signalling by the Relay Output 6
Open/Close Disabling 7
Signalling panel 7
ANSI Functions 7
ADDRESSES OF THE DIGITAL SIGNALS AND THE MEASUREMENTS 8
Measurements 8
Digital Signals 9
PROTECTIONS 15
Parameterization 15
Common parameters 16
General Overcurrent Protection 17
Overvoltage Protection 20 Undervoltage Protection 21
Overfrequency Protection 22
Underfrequency Protection 23
Earth Fault Protection 24
Impulse Protection 25
Conductance Protection 26
Wattmetrical Protection 26
Earth Fault Protection – Connection of the Resistor 27
Voltage Unbalance Protection 28
Current Unbalance Protection 29
AUTOMATICS 31
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Protections and Automatics 3V3I
Automatic Open after Unsuccessful Reclosing 31
Automatic Reclosing 32
FAULT RECORDS 34
Common Settings 34
Analogue Channels 35
Digital Channels 35
SIGNALLING 36
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Protections and Automatics 3V3I
IntroductionDear customer, this document explains the protections and automatics functions that are implemented in RTU7 based units
manufactured by the company ELVAC a.s. The document contains a description of the particular protection functions and their
parameters. The RTU User Center application is used for parameterization of the RTU units.
Technical Support
Our goal in writing this document was to create a clear guide for the users of our equipment. If you find a problem or experience
any difficulties, please contact our technical support. Our technical support team is ready to explain any incomprehension. This
document is continuously updated, so please check if your version is up to date.
Training
We offer training on protections and the other functions of the RTU units for our customers. If you are interested, please contact a
product manager.
Copyright
Modifications or provision of the content to a third party in any form and without the expressive consent of the ELVAC a.s. is
forbidden.
Copyright © 2009-2013 ELVAC a.s.
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Protections and Automatics 3V3I
MeasurementThe following chapters describe the algorithms used for the measuring and for the calculation of the particular values.
Sampling
The RTU unit measures three phase voltages and three phase currents. Currents are measured by two inputs with two different
input ranges (currents ix and ixH). Thanks to this feature the accurate values are measured up to a quadruple of the nominal current.
Nominal range depends on the used input analogue module. A 10bit A/D converter with simultaneous sampling is used to avoid the
phase shift among the measured channels. Additionally the phase shift compensation is carried out during the production process.
All currents and voltages are sampled 180 times per 10 milliseconds. 3i0 and v0 are calculated every 10ms/180 as the sum of the
instantaneous values of the phase currents and phase voltages. All instantaneous values of currents and voltages are filtered by
band pass from 30 Hz to 80 Hz. These filtered values are used for the computation of i 0 and v0 and also for the computation of the
effective values of 3I0 and V0. The measured values are processed 180 times per 10 milliseconds. The effective values are calculated
every 10 milliseconds. These values are used in the protection functions. The one second average from 100 values is transmitted to
the control system if the integral or differential filter is exceeded, or if the limit is exceeded.
Angles
Angles are measured 180 times per 10 milliseconds (with 1° step). The angles 1/2/3 are measured between the phase currentsand the phase voltages. When the effective value of V1/V2/V3 is less than 1% (of the voltage range) and the effective value of I 1/ I2/ I3
is less than 0.5 % (of the current range), the angle is not measured and it is set to 0° (cos 0° = 1).
The angle 0 is measured between v0 and -i0. The filtered values of v0 and -i0 are used (see next chapter). The angle is measured
constantly. However cos 0 = 1 is transmitted to the control system if the one second average of the effective value of the V0 is lessthan 1.08% (of the voltage range) or if the one second average of the effective value of 3I0 is less than 0.78% (of the current range).
Filtration
The instantaneous values ux and ix are filtered by the band pass from 30 Hz to 80 Hz. The phase shift of the output signal is the same
as the input signal. The filter transfer is compensated by the constant.
Frequency Measurement
Frequency is measured from the positive sequence voltage which is given by V PS = (V1 + aV2 + a2V3)/3, where a = e
j2/3. The measured
range is from 10 to 100 Hz. The frequency is measured by counting of the zero crosses of the vPS
. The frequency is set to 0 Hz, when
all line to line voltages are less than 10% of the voltage range. The range of the frequency for the control system is from 0 to 100 Hz
(for the normalized values in the range from 0 to 32767). The smallest step is 0.024 Hz. Accuracy of the frequency is ±0.07 % (i.e.
±0.035 Hz for 50 Hz) for frequencies between 30 Hz and 80 Hz.
Transmitting Measured Values
Actual values are transmitted when the integral or differential filter is exceeded. Group transfer is also available. When any of the
analogue channels with enabled group transfer changes then all analogue channels with enabled group transfer are transmitted.
Thanks to this feature the amount of transmitted data can be reduced. Moreover, the transmitted values are read at the same time.
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Protections and Automatics 3V3I
Ranges
The ranges for protections are the same as the ranges for the current and voltage inputs. All ranges and parameters are set in the
effective values. The following table contains ranges for both current and voltage inputs. The set value and the maximum value vary
according to the nominal value. Values in the rows “without conversion” remain unchanged.
Nominal range Set range Maximum value
Current inputs [A] 100 400 400
Current inputs (without conversion) 8192 32767 32767
Voltage inputs [kV] 22 26.4 26.4Voltage inputs (without conversion) 27306 32767 32767
Powers Measurement
The RTU7 units measure active, reactive, and apparent power. Active power is given by the sum of the products of the
instantaneous currents and voltages in all three phases. Reactive power is given by the sum of the products of the instantaneous
currents and voltages in all three phases where voltages are shifted by 90°. Apparent power is calculated every 10 milliseconds from
the active and reactive power. The range for the powers P, Q, S is from 0 to 3 * U * I.
Circuit Breaker Control
Circuit breaker can be controlled by the relay output. One relay output is defined for the open command of the circuit breaker andthe second is defined for the close command. Two additional parameters are used to define one and a half or two pole control.
Open command has a greater priority than the close one. When the open command is performed during the close command the
close command is interrupted.
Group Switching
The RTU7 unit in the 3V3I configuration provides two groups of protections. Only one group is used at a time. Switching between
groups is done by the special signal with address 161. The currently used group is determined by the value of this signal. The
protections are initialized after the group is switched.
Initialization
Initialization of the protections takes place after the unit restart, switching on, parameterization, and group switching. Theinitialization lasts 15 seconds. The signalling of pickups, trips, closing, and opening is disabled during the initialization. All pickups
and trips are cleared and parameters are read at the beginning of initialization.
Signalling
Particular protections can signal pickups, trips and opening by signals. The signals have to be enabled to transmit its states to the
control system. It is also possible to define additional parameters (single/double bit, enable negation) for each signal. The signals are
transmitted with not topical attribute if the protection is disabled.
Signalling by the Relay Output
Trip of all protection can be signalled by relay closing. This must be enabled in the parameters of the particular protection. If the
address of the signalling relay is set to none, the signalling is disabled. The signalling by relay is also disabled when the address of the
signalling relay equals to the address of the breaker close relay, or breaker open relay, or heating relay, or cooling relay. Signalling
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Protections and Automatics 3V3I
by relay is prolonged by 40 ms because of possible flicking of the trip. The same relay may be shared among more protection
functions. The resulting state of the relay is given by the logical sum of particulars trips.
Open/Close Disabling
Open or close function provided by the protection can be blocked (disabled) by parameters and by the special virtual digital signals.
These signals are set to block (its value is 1) open/close function by default. The logic of all virtual digital inputs including the special
blocking signals for protections can be negated.
Signalling panel
The LED signalling panel can be connected to the RTU7 unit. The meaning of each LED is parameterized by the expressions.
ANSI Functions
In the following table there is a list of the ANSI function codes and its descriptions that are used in this document.
Function number Description
ANSI 50 Phase overcurrent protection
ANSI 51 Time phase overcurrent protection
ANSI 50N Earth fault protection
ANSI 51N Time earth fault protection
ANSI 67 Directional phase overcurrent protection
ANSI 67N Directional earth fault protectionANSI 59 Phase to phase overvoltage protection
ANSI 59N Neutral voltage displacement
ANSI 27 Phase to phase undervoltage protection
ANSI 81H Overfrequency protection
ANSI 81L Underfrequency protection
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Protections and Automatics 3V3I
Addresses of the Digital Signals and the MeasurementsAll signals and measurements provided by the RTU7 unit in the 3V3I configuration are described in the following table.
Measurements
Inputs
Address Description Range
0 I1 0 to IMAX
1 I2 0 to IMAX 2 I3 0 to IMAX
3 I - average I1, I2, I3 0 to IMAX
4 3I0 (filtered) 0 to IMAX
5 Vf1 0 to VMAX
6 Vf2 0 to VMAX
7 Vf3 0 to VMAX
8 Vf - average Vf1, Vf2, Vf3 0 to VMAX
9 V0 (filtered) 0 to VMAX
10 V12 0 to VMAX
11 V23 0 to VMAX 12 V31 0 to VMAX
13 VS – average V12 ,V23 ,V31 0 to VMAX
14 P 0 to 3 * IMAX * VMAX
15 Q 0 to 3 * IMAX * VMAX
16 S 0 to 3 * IMAX * VMAX
17 cos 0 to 1
20 cos 0 0 to 1
21 Frequency 0 to 100 Hz
121 Maximum processor utilization since last reset (0 to 100%) 0 to 100 %
122 Actual processor utilization in the last second (0 to 100%) 0 to 100 %
123 Accumulator capacity 0 to 100 %
124 Accumulator voltage 0 to 30 V
125 Power supply voltage 0 to 60 V
126 External temperature 0 to 130 °C
127 Internal temperature 0 to 130 °C
128 Fault records number 0 to 32767
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Protections and Automatics 3V3I
Digital Signals
Inputs
Address Description
0 to 19 Physical digital inputs
104 Change buffer overflow
105 Unit reset
106 Power supply failure
107 State of the cooling relay (0 when cooling is not enabled)
108 State of the heating relay (0 when heating is not enabled)
109 Accumulator charging failure
110 Reserve
111 Records error (wrong CRC of records or calibrations)
112 Reserve
113 Reserve
114 Protections group 2 error (wrong CRC of protections or calibrations)
115 Protections group 1 error (wrong CRC of protections or calibrations)
116 Error – 1 = limited functionality , 0 = everything is OK
117 Error of the inputs/outputs parameters – 1 error (wrong CRC), 0 = Parameters are OK118 Error of the system parameters – 1 = error (wrong CRC), 0 = Parameters are OK
119 Low accumulator – 0 = accumulator capacity is OK, 1 = accumulator capacity is low
120 Copy of the DI1
121 Copy of the DI0
122 Protections error – 1 = protections are disabled (wrong CRC of protections or calibrations)
123 Time source – 0 = control system, 1 = device on the bus, 2 = external source
125 Modem reset
126 Power supply lost
127 Automatic power off in 60 seconds
128 Disabled open by any protection129 Disabled open by general overcurrent protection 1
st group
130 Disabled open by general overcurrent protection 2nd
group
131 Disabled open by general overcurrent protection 3rd
group
132 Disabled open by general overcurrent protection 4th
group
133 Disabled open by general overcurrent protection 5th
group
134 Disabled open by general overcurrent protection 6th
group
135 Disabled open by general overcurrent protection 7th
group
136 Disabled open by general overcurrent protection 8th
group
137 Disabled open by overvoltage protection 1st
group
138 Disabled open by overvoltage protection 2nd
group
139 Disabled open by overvoltage protection 3rd
group
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140 Disabled open by undervoltage protection 1st
group
141 Disabled open by undervoltage protection 2nd
group
142 Disabled open by overfrequency protection 1st
group
143 Disabled open by overfrequency protection 2nd
group
144 Disabled open by underfrequency protection 1st
group
145 Disabled open by underfrequency protection 2nd
group
146 Disabled signalling of voltage unbalance
147 Disabled open by voltage unbalance protection
148 Disabled signalling of current unbalance
149 Disabled open by current unbalance protection
150 Disabled open by earth fault protection
151 Disabled open after unsuccessful reclosing
152 Disabled close by automatic reclosing (AR)
153AR status: 0 = off, 1 = fast (1
st cycle enabled, 2
nd cycle disabled),
2 = slow (1st
cycle enabled, 2nd
cycle enabled), 3 = fast + slow (1st
and 2nd
cycles enabled)
154 AR disabled (controlling by signals has to be enabled in the parameters of the AR)
155 AR fast (controlling by signals has to be enabled in the parameters of the AR)
156 AR slow (controlling by signals has to be enabled in the parameters of the AR)
157 AR fast + slow (controlling by signals has to be enabled in the parameters of the AR)158 Simulations enabled
159 Manual accumulator test
160 Remote clear of the front panel (on the RTU7K unit)
161 2n
protection group selected
162 Erase all fault records stored in the unit
163 Manual record start
255 Signal without meaning – can be used for test purposes
256 Pickup of general overcurrent protection – I1 – 1st
group
257 Pickup of general overcurrent protection – I2 – 1st
group
258 Pickup of general overcurrent protection – I2 – 1
st
group 259 Pickup of general overcurrent protection (I0 or I1 or I2 or I3) – 1
st group
260 Trip of general overcurrent protection – I1 – 1st
group
261 Trip of general overcurrent protection – I2 – 1st
group
262 Trip of general overcurrent protection – I2 – 1st
group
263 Trip of general overcurrent protection (I0 or I1 or I2 or I3) – 1st
group
264 Close by general overcurrent protection – 1st
group (0→1→0)
265 Pickup of general overcurrent protection – I1 – 2nd
group
266 Pickup of general overcurrent protection – I2 – 2nd
group
267 Pickup of general overcurrent protection – I3 – 2nd
group
268 Pickup of general overcurrent protection (I0 or I1 or I2 or I3) – 2nd
group
269 Trip of general overcurrent protection – I1 – 2nd
group
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270 Trip of general overcurrent protection – I2 – 2nd
group
271 Trip of general overcurrent protection – I3 – 2nd
group
272 Trip of general overcurrent protection (I0 or I1 or I2 or I3) – 2nd
group
273 Close by general overcurrent protection – 2nd
group (0→1→0)
274 Pickup of general overcurrent protection – I1 – 3rd
group
275 Pickup of general overcurrent protection – I2 – 3rd
group
276 Pickup of general overcurrent protection – I3 – 3rd
group
277 Pickup of general overcurrent protection (I0 or I1 or I2 or I3) – 3rd
group
278 Trip of general overcurrent protection – I1 – 3rd group
279 Trip of general overcurrent protection – I2 – 3rd
group
280 Trip of general overcurrent protection – I3 – 3rd
group
281 Trip of general overcurrent protection (I0 or I1 or I2 or I3) – 3rd
group
282 Close by general overcurrent protection – 3rd
group (0→1→0)
283 Pickup of general overcurrent protection – I1 – 4th
group
284 Pickup of general overcurrent protection – I2 – 4th
group
285 Pickup of general overcurrent protection – I3 – 4th
group
286 Pickup of general overcurrent protection (I0 or I1 or I2 or I3) – 4th
group
287 Trip of general overcurrent protection – I1 – 4th
group
288 Trip of general overcurrent protection – I2 – 4th
group289 Trip of general overcurrent protection – I3 – 4
th group
290 Trip of general overcurrent protection (I0 or I1 or I2 or I3) – 4th
group
291 Close by general overcurrent protection – 4th
group (0→1→0)
292 Pickup of general overcurrent protection – I1 – 5th
group
293 Pickup of general overcurrent protection – I2 – 5th
group
294 Pickup of general overcurrent protection – I3 – 5th
group
295 Pickup of general overcurrent protection (I0 or I1 or I2 or I3) – 5t
group
296 Trip of general overcurrent protection – I1 – 5t
group
297 Trip of general overcurrent protection – I2 – 5t
group
298 Trip of general overcurrent protection – I3 – 5
t
group 299 Trip of general overcurrent protection (I0 or I1 or I2 or I3) – 5
t group
300 Close by general overcurrent protection – 5t
group (0→1→0)
301 Pickup of general overcurrent protection – I1 – 6th
group
302 Pickup of general overcurrent protection – I2 – 6th
group
303 Pickup of general overcurrent protection – I3 – 6th
group
304 Pickup of general overcurrent protection (I0 or I1 or I2 or I3) – 6th
group
305 Trip of general overcurrent protection – I1 – 6th
group
306 Trip of general overcurrent protection – I2 – 6th
group
307 Trip of general overcurrent protection – I3 – 6th
group
308 Trip of general overcurrent protection (I0 or I1 or I2 or I3) – 6th
group
309 Close by general overcurrent protection – 6th
group (0→1→0)
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310 Pickup of general overcurrent protection – I1 – 7th
group
311 Pickup of general overcurrent protection – I2 – 7th
group
312 Pickup of general overcurrent protection – I3 – 7th
group
313 Pickup of general overcurrent protection (I0 or I1 or I2 or I3) – 7th
group
314 Trip of general overcurrent protection – I1 – 7th
group
315 Trip of general overcurrent protection – I2 – 7th
group
316 Trip of general overcurrent protection – I3 – 7th
group
317 Trip of general overcurrent protection (I0 or I1 or I2 or I3) – 7th
group
318 Close by general overcurrent protection – 7th group (0→1→0)
319 Pickup of general overcurrent protection – I1 – 8th
group
320 Pickup of general overcurrent protection – I2 – 8th
group
321 Pickup of general overcurrent protection – I3 – 8th
group
322 Pickup of general overcurrent protection (I0 or I1 or I2 or I3) – 8th
group
323 Trip of general overcurrent protection – I1 – 8th
group
324 Trip of general overcurrent protection – I2 – 8th
group
325 Trip of general overcurrent protection – I3 – 8th
group
326 Trip of general overcurrent protection (I0 or I1 or I2 or I3) – 8th
group
327 Close by general overcurrent protection 8th
group (0→1→0)
328 Pickup of overvoltage protection 1st
group329 Trip of overvoltage protection 1
st group
330 Open by overvoltage protection 1st
group (0→1→0)
331 Pickup of overvoltage protection 2nd
group
332 Trip of overvoltage protection 2nd
group
333 Open by overvoltage protection 2nd
group (0→1→0)
334 Pickup of overvoltage protection 3rd
group
335 Trip of overvoltage protection 3r
group
336 Open by overvoltage protection 3r
group (0→1→0)
337 Pickup of undervoltage protection 1st
group
338 Trip of undervoltage protection 1
st
group339 Open by undervoltage protection 1
st group (0→1→0)
340 Pickup of undervoltage protection 2n
group
341 Trip of undervoltage protection 2nd
group
342 Open by undervoltage protection 2nd
group (0→1→0)
343 Pickup of overfrequency protection 1st
group
344 Trip of overfrequency protection 1st
group
345 Open by overfrequency protection 1st
group (0→1→0)
346 Pickup of overfrequency protection 2nd
group
347 Trip of overfrequency protection 2nd
group
348 Open by overfrequency protection 2nd
group (0→1→0)
349 Pickup of underfrequency protection 1st
group
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350 Trip of underfrequency protection 1st
group
351 Open by underfrequency protection 1st
group (0→1→0)
352 Pickup of underfrequency protection 2nd
group
353 Trip of underfrequency protection 2nd
group
354 Open by underfrequency protection 2nd
group (0→1→0)
355 Pickup of voltage unbalance
356 Trip of voltage unbalance
357 Open by voltage unbalance (0→1→0)
358 Pickup current unbalance
359 Trip current unbalance
360 Open by current unbalance (0→1→0)
361 Pickup of earth fault protection
362 Trip of earth fault protection
363 Open by earth fault protection (0→1→0)
364 Open after unsuccessful automatic reclosing (0→1→0)
365 Close by automatic reclosing (0→1→0)
366 Voltage B
367 Fault records buffer overrun
368 Simulation in progress (some input can be in the simulated state)
Outputs
Address Description
0 to 19 Relay 0 to 19
128 Disable open by any protection
129 Disable open by general overcurrent protection 1st
group
130 Disable open by general overcurrent protection 2n
group
131 Disable open by general overcurrent protection 3r
group
132 Disable open by general overcurrent protection 4t
group133 Disable open by general overcurrent protection 5
t group
134 Disable open by general overcurrent protection 6t
group
135 Disable open by general overcurrent protection 7th
group
136 Disable open by general overcurrent protection 8th
group
137 Disable open by overvoltage protection 1st
group
138 Disable open by overvoltage protection 2nd
group
139 Disable open by overvoltage protection 3rd
group
140 Disable open by undervoltage protection 1st
group
141 Disable open by undervoltage protection 2nd
group
142 Disable open by overfrequency protection 1
st
group143 Disable open by overfrequency protection 2
nd group
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144 Disable open by underfrequency protection 1st
group
145 Disable open by underfrequency protection 2nd
group
146 Disable signalling of voltage unbalance
147 Disable open by voltage unbalance protection
148 Disable signalling of current unbalance
149 Disable open by current unbalance protection
150 Disable open by earth fault protection
151 Disable open after unsuccessful reclosing
152 Disable close by automatic reclosing (AR)
153 Set AR: 0 = off, 1 = fast (1st
cycle enabled, 2nd
cycle disabled),
2 = slow (1st
cycle enabled, 2nd
cycle enabled), 3 = fast + slow (1st
and 2nd
cycles enabled)
154 Disable AR (controlling by signals has to be enabled in the parameters of the AR)
155 Set fast AR (controlling by signals has to be enabled in the parameters of the AR)
156 Set slow AR (controlling by signals has to be enabled in the parameters of the AR)
157 Set fast + slow AR (controlling by signals has to be enabled in the parameters of the AR)
158 Enable simulations
159 Start manual accumulator test
160 Clear the front panel (on the RTU7K unit)
161 Select protection group162 Erase all fault records stored in the unit
163 Manual record start
255 Signal without meaning – can be used for test purposes
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Common parameters
Description
Common parameters contain a set of parameters that are used across many particular protections.
Parameters
Main Parameters
Enabled YES/NO Enables/disables protection functions.
Channel 0, 1 0 = 1st
protection block, 1 = 2nd
protection block (typically backup).Conversion
Values conversion YES/NO Enables/disabled conversion of analogue values according to the ranges
in the RTU User Center application.
Voltage range VMAX Range of the voltage (depends on used input module and sensor).
Voltage unit V, kV, … Unit of the voltage.
Current range IMAX Range of the current (depends on used input module and sensor).
Current unit mA, V, … Unit of the current.
Conductance range IMAX / VMAX Range of the conductance.
Conductance unit uS, mS, … Unit of the conductance.
Circuit Breaker
Address of circuit breaker status
signal
0 to 19 The address of digital inputs to which the circuit breaker is connected.
This digital input has to be set as double point. The first input of the
double point input signals that the circuit breaker is open. The second
input signals that the circuit breaker is closed.
Address of circuit breaker open relay 0 to 19, none It defines the address of relay that is used for opening circuit breaker
(none = Open by protection is disabled).
Duration of open relay activation 0 to 2.55 s
Step 0.01 s
It defines the time interval how long the open relay is connected in the
case of opening.
Address of circuit breaker close relay 0 to 19, none It defines the address of relay that is used for closing circuit breaker
(none = Close by protection is disabled).
Duration of close relay activation 0 to 2.55 s
Step 0.01 s
It defines the time interval how long the close relay is connected in the
case of closing.
Address of circuit breaker aux. open
relay
0 to 19, none It defines the address of relay that is used together with the open relay.
The one and half (this address is equal with the Address of circuit
breaker aux. close relay) or two pole control can be enabled by defining
this relay.
Address of circuit breaker aux. close
relay
0 to 19, none It defines the address of relay that is used together with the close relay.
The one and half (this address is equal with the Address of circuit
breaker aux. open relay) or two pole control can be enabled by defining
this relay.
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General Overcurrent Protection
ANSI 50, 51, 67, 50N, 51N, 67N
Description
General overcurrent protection is processed every 10 milliseconds. Eight independent protection groups are available. Each group
has its own parameters and signals. General overcurrent protection can work according to ANSI 50, 51, 67, 50N, 51N, 67N from the
standard IEC 60255-151:2009. The dropout value equals 97% of the Current limit IS.
The fault direction is determined by the polarity of active power in fault phase for phase protection or by the polarity of active
power P0 for earth fault protection. Active power is calculated from the fundamental frequency. Voltage memory is used when the
measured voltage during the fault is too small (less than 20% of its range). The voltage memory capacity is one second. The fault is
in the “forward” direction when the active power is positive. The fault is in the “backward” direction when the active power is
negative or zero.
After the circuit breaker is closed the second, typically greater, limit of the current Raised current threshold after close is used. The
second limit is valid only for a finite time that is set by the parameter Raised threshold duration. The circuit breaker close status is
determined from the circuit breaker status signal. The remote close command is also considered as a circuit breaker close status.
The second current limit is enabled only if the values of all the three line to line voltages are greater than Voltage to allow raised
threshold.
The protection works with filtered value of I0 if the parameter
Protection type is set to Earth. Pickup is set when V
0 is greater than
Lower threshold of voltage V0 and I0 is greater than IS. Trip is set when the pickup is set for the time given by selected time
characteristics. Pickup and trip are cleared when IX is less than 97% IS and V0 is less than 97% of Lower threshold of voltage V0 for
the time given by selected time characteristics.
The protection works with phase values I1, I2, I3 if the parameter Protection type is set to Phase. The filtration of values is enabled by
the parameter Filter. The pickup is set when IX is greater than IS. The trip is set when the pickup is set for the time given by selected
time characteristics. The pickup and trip are cleared when IX is less than 97% IS for the time given by selected time characteristics.
The protection opens the circuit breaker, when the trip is set. The open control of the circuit breaker is enabled if the value of the
parameter Open by protection is YES and the signals blocking open function are set to 0.
The trip can also be signalled by the relay output (see chapter Signalling by the Relay OutputSignalling by the Relay OutputSignalling
by the Relay Output). The address of the signal relay is defined by the parameter Address of trip signal relay.
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Time characteristics are as follows.
Characteristics Pickup time
Dropout time
Characteristics name
k [s] c [s] tr A 0.14 0 0.02 4.85 2 Standard inverse
B 13.5 0 1 21.6 2 Very inverseC 50 0 2 29.1 2 Extremely inverse
D 0.0515 0.114 0.02 4.85 2 IEEE moderately inverse
E 19.61 0.491 2 21.6 2 IEEE very inverse
F 28.2 0.121 2 29.1 2 IEEE extremely inverse
Parameters
Main Parameters
Enabled YES/NO Enables/disables this protection.
Limits
Current limit IS 0 to IMAX Pickup current limit IS that is used for calculation of the pickup time.
Min. duration of threshold break 0 to 655.35 s
Step 0.01 s
The parameter for non-directional characteristics. The trip is set after the
pickup is set for the time defined by this parameter.
Time multiplier 0 to 2
Step 0.01
This parameter defines time multiplier TMS for time dependent
characteristics.
Raised current threshold after close 0 to IMAX Typically raised current limit that is used instead of the IS after the circuit
breaker close.
Raised threshold duration 0 to 25.5 s
Step 0.1 s
This parameter defines the time for which the raised limit is valid.
Voltage to allow raised threshold 0 to VMAX The raised limit is valid only in case that all line to line voltages are
greater than this parameter.
Lower threshold of voltage V0 0 to VMAX This parameter is used for earth fault protection. The earth faultprotection is enabled when V0 is grater then value of this parameter.
Time reset 0 to 2.55 s
Step 0.01 s
The parameter for non-directional characteristics. The pickup and trip is
cleared when the current is less than 97% of IS for the time defined by
this parameter.
Protection directivity Non-directional
Forward
Backward
Directionality of the protection is selected by this parameter. The
protection can work as non-directional (works in both directions), or it
can works in the forward direction (active power is positive), or it can
works in the backward direction (active power is negative or zero).
Characteristic Time
independent
A to F
This parameter is used to select time characteristic for this protection.
Time independent and six standardized characteristics (see table above)
are configurable.
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Filter
Filter YES/NO The protection process filtered values of current when this parameter is
to YES. Otherwise it process unfiltered values. The earth protection
works with filtered value I0 always.
Automatics
Open by protection YES/NO Enables/disables opening by this protection.
Number of reclosing after overcurrent 0 to 5 This parameter defines maximum number of automatic reclosing.
Signalling
Address of trip signal relay 0 to 19, none This parameter defines the address of the relay for signalling of trip.
Evaluate Inputs
Protection type Phase
Earth
The protection uses phase values I1, I2, and I3 when the value of this
parameter is Phase, of it uses I0 (earth fault protection) when the value
of this parameter is Earth.
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Overvoltage Protection
ANSI 59, 59N
Description
Overvoltage protection is processed every 10 milliseconds. Effective values of phases, line to line, or V 0 voltages (it depends on the
value of parameter Evaluated inputs) are compared with Voltage limit. Pickup is set if compared voltage is greater than Voltage
limit. Trip is set when the pickup is set for the time given by the parameter Min. duration of threshold break. Pickup and trip are
cleared when compared voltage is less than Lower voltage limit (its value is typically about 95% of the Voltage limit). Two
independent protection groups with its own parameters and signals are available.
The protection opens the circuit breaker, when the trip is set. The open control of the circuit breaker is enabled if the value of the
parameter Open by protection is YES and the signals blocking open function are set to 0.
The trip can also be signalled by the relay output (see chapter Signalling by the Relay OutputSignalling by the Relay OutputSignalling
by the Relay Output). The address of the signal relay is defined by the parameter Address of trip signal relay.
Parameters
Main Parameters
Enabled YES/NO Enables/disables this protection.
Limits
Voltage limit 0 to VMAX Pickup is set when compared voltage is greater than this value.
Min. duration of threshold break 0 to 655.35 s
Step 0,01 s
Trip is set when the pickup is set for the time given by this parameter.
Lower voltage limit 0 to VMAX Pickup and trip are cleared when compared voltage is less than this
value.
Automatics
Open by protection YES/NO Enables/disables opening by this protection.
Signalling
Address of trip signal relay 0 to 19, none This parameter defines the address of the relay for signalling of trip.
Evaluated Inputs
Evaluated inputs V1/V2/V3 V1, V2, V3
V12, V23, V31
V0
Processed inputs are selected by this parameter.
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Undervoltage Protection
ANSI 27
Description
Undervoltage protection is processed every 10 milliseconds. Effective values of phases, line to line, or V0 voltages (it depends on the
value of parameter Evaluated inputs) are compared with Voltage limit. Pickup is set if compared voltage is less than Voltage limit.
Trip is set when the pickup is set for the time given by the parameter Min. duration of threshold break. Pickup and trip are cleared
when compared voltage is greater than Upper voltage limit (its value is typically about 105% of the Voltage limit). The processing of
this protection is disabled and all signals are cleared when all phase currents are less than Limit of minimal current. Twoindependent protection groups with its own parameters and signals are available.
The protection opens the circuit breaker, when the trip is set. The open control of the circuit breaker is enabled if the value of the
parameter Open by protection is YES and the signals blocking open function are set to 0.
The trip can also be signalled by the relay output (see chapter Signalling by the Relay OutputSignalling by the Relay OutputSignalling
by the Relay Output). The address of the signal relay is defined by the parameter Address of trip signal relay.
Parameters
Main Parameters
Enabled YES/NO Enables/disables this protection.
Limits
Voltage limit 0 to VMAX Pickup is set when compared voltage is less than this value and any
phase current is greater than Limit of minimal current.
Min. duration of threshold break 0 to 655.35 s
Step 0.01 s
Trip is set when the pickup is set for the time given by this parameter.
Upper voltage limit 0 to VMAX Pickup and trip are cleared when compared voltage is greater than this
value.
Limit of minimal current 0 to IMAX Phase current above this limit enables this protection.
Automatics
Open by protection YES/NO Enables/disables opening by this protection.
SignallingAddress of trip signal relay 0 to 19, none This parameter defines the address of the relay for signalling of trip.
Evaluated Inputs
Evaluated inputs V1/V2/V3
V1, V2, V3
V12, V23, V31
Processed inputs are selected by this parameter.
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Overfrequency Protection
ANSI 81H
Description
Overfrequency protection is processed every 10 milliseconds. Pickup is set if measured frequency is greater than Frequency limit
and voltage of all three line to line voltages is greater than Phase to phase voltage limit. Trip is set when the pickup is set for the
time given by the parameter Min. duration of threshold break. Pickup and trip are cleared when the frequency is less than Lower
limit of frequency (its value is typically about 95% of the Frequency limit) or any of line to line voltage is less than Phase to phase
voltage limit. Two independent protection groups with its own parameters and signals are available.
The protection opens the circuit breaker, when the trip is set. The open control of the circuit breaker is enabled if the value of the
parameter Open by protection is YES and the signals blocking open function are set to 0.
The trip can also be signalled by the relay output (see chapter Signalling by the Relay OutputSignalling by the Relay OutputSignalling
by the Relay Output). The address of the signal relay is defined by the parameter Address of trip signal relay.
Parameters
Main Parameters
Enabled YES/NO Enables/disables this protection.
Limits
Frequency limit 0 to 100 Hz
Step 0.003 Hz
Pickup is set if measured frequency is greater than this parameter and
voltage of all three line to line voltages is greater than Phase to phase
voltage limit.
Min. duration of threshold break 0 to 25.5 s
Step 0.1 s
Trip is set when the pickup is set for the time given by this parameter.
Lower limit of frequency 0 to 100 Hz
Step 0.003 Hz
Pickup and trip are cleared if the frequency is less than this parameter.
Phase to phase voltage limit 0 to VMAX Any phase to phase voltage under this limit disables this protection.
Automatics
Open by protection YES/NO Enables/disables opening by this protection.
SignallingAddress of trip signal relay 0 to 19, none This parameter defines the address of the relay for signalling of trip.
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Underfrequency Protection
ANSI 81L
Description
Underfrequency protection is processed every 10 milliseconds. Pickup is set if measured frequency is less than Frequency limit and
voltage of all three line to line voltages is greater than Phase to phase voltage limit. Trip is set when the pickup is set for the time
given by the parameter Min. duration of threshold break. Pickup and trip are cleared when the frequency is greater than Upper
limit of frequency (its value is typically about 105% of the Frequency limit) or any of line to line voltage is less than Phase to phase
voltage limit. Two independent protection groups with its own parameters and signals are available.
The protection opens the circuit breaker, when the trip is set. The open control of the circuit breaker is enabled if the value of the
parameter Open by protection is YES and the signals blocking open function are set to 0.
The trip can also be signalled by the relay output (see chapter Signalling by the Relay OutputSignalling by the Relay OutputSignalling
by the Relay Output). The address of the signal relay is defined by the parameter Address of trip signal relay.
Parameters
Main Parameters
Enabled YES/NO Enables/disables this protection.
Limits
Frequency limit 0 to 100 Hz
Step 0.003 Hz
Pickup is set if measured frequency is less than this parameter and
voltage of all three line to line voltages is greater than Phase to phase
voltage limit.
Min. duration of threshold break 0 to 25.5 s
Step 0.1 s
Trip is set when the pickup is set for the time given by this parameter.
Upper limit of frequency 0 to 100 Hz
Step 0.003 Hz
Pickup and trip are cleared if the frequency is greater than this
parameter.
Phase to phase voltage limit 0 to VMAX Any phase to phase voltage under this limit disables this protection.
Automatics
Open by protection YES/NO Enables/disables opening by this protection.
SignallingAddress of trip signal relay 0 to 19, none This parameter defines the address of the relay for signalling of trip.
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Earth Fault Protection
Earth fault protection contains several independent evaluation principles. The common parameters have to be set firstly then the
parameters of each principle have to be set. Following internal statues related to earth fault protection are used in this document:
ZS-I – Trip of the impulse principle
ZS-K – Trip of the conductance principle
ZS-R – Trip of the connection of the resistor principle
ZS-W – Trip of the wattmetrical principle
ZS-V0 – V0 is greater than Lover threshold of voltage V0
Description
Pickup is set if any of the internal statuses ZS-I, ZS-K, ZS-R, ZS-W, ZS-V0 is set. Trip is set when the pickup is set for the time given by
the parameter Time before open. Pickup and trip are cleared when all internal statuses are clear for the time given by parameter
the Prolongation of earth fault signalling. Pickup and trip are cleared also when all internal statuses are clear and the circuit
breaker is opened.
The protection opens the circuit breaker, when the trip is set. The open control of the circuit breaker is enabled if the value of the
parameter Open by protection is YES and the signals blocking open function are set to 0.
The trip can also be signalled by the relay output (see chapter Signalling by the Relay OutputSignalling by the Relay OutputSignalling
by the Relay Output). The address of the signal relay is defined by the parameter Address of trip signal relay.
Internal status ZS-V0 is set when V0 is greater of equal to Lover threshold of voltage V0. When V0 is less than Lover threshold of
voltage V0, internal status ZS-V0 is cleared.
Parameters
Main Parameters
Enabled YES/NO Enables/disables this protection.
Limits
Lover threshold of voltage V0 0 to VMAX Internal status ZS-V0 is set when V0 is greater of equal to this parameter.
This parameter is also used for clearing internal statuses.
AutomaticsOpen by protection YES/NO Enables/disables opening by this protection.
Time before open 0 to 25.5 s
Step 0.1 s
Trip is set when the pickup is set for the time given by this parameter.
Number of reclosing after earth fault 0 to 5 This parameter defines maximum number of automatic reclosing.
Signalling
Prolongation of earth fault signalling 0 to 25.5 s
Step 0.1 s
Signalling of the trip and pick up is prolonged for the time given by this
parameter. Setting this parameter reduces possible flicking of the tri and
pickup.
Address of trip signal relay 0 to 19, none This parameter defines the address of the relay for signalling of trip.
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Impulse Protection
Description
Impulse earth protection is processed every 1 millisecond. For positive active power it is tested if (-i 0 * v0) > 0 and absolute value of
v0 is greater than Voltage V0 threshold and absolute value of 3i0 is greater than Current 3I0 threshold. For negative active power it is
tested if (i0 * v0) > 0 and absolute value of v0 is greater than Voltage V0 threshold and absolute value of 3i0 is greater than Current
3I0 threshold. Internal status ZS-I is set when all three conditions mentioned above are true for the time given by the parameter
Time of check. Internal status ZS-I is cleared when any of conditions above is not true and V 0 is less than Lover threshold of voltage
V0 from common parameters. The direction of the active power is evaluated every 1 second. Active power is considered as positiveif its value is greater than 0.4% of its range. Active power is considered as negative if its value is less than -0.4% of its range. If the
value of active power is between -0.4% and 0.4%, the sign of the active power remains unchanged.
Parameters
Main Parameters
Enabled YES/NO Enables/disables this protection.
Limits
Voltage V0 threshold 0 to VMAX V0 must be greater than this parameter in order to set ZS-I.
Current 3I0 threshold 0 to IMAX 3I0 must be greater than this parameter in order to set ZS-I.
Time of check 0 to 255 ms
Step 1 ms
Internal status ZS-I is set if all conditions are true for the time given by
this parameter.
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Conductance Protection
Description
Conductance earth protection is processed every 10 milliseconds. Internal status ZS-K is set when V0 > Voltage V0 threshold and 3I0
* cos(0) / V0 > Conductance threshold for the time given by the parameter Time of check. Internal status ZS-K is cleared when anyof conditions above is not true and V0 is less than Lover threshold of voltage V0 from common parameters.
Parameters
Main ParametersEnabled YES/NO Enables/disables this protection.
Limits
Voltage V0 threshold 0 to VMAX V0 must be greater than this parameter in order to set ZS-K.
Conductance threshold 0 to IMAX / VMAX Conductance must be greater than this parameter in order to set ZS-K.
Time of check 0 to 2.55 s
Step 0.01 s
Internal status ZS-K is set if all conditions are true for the time given by
this parameter.
Wattmetrical Protection
Description
Wattmetrical earth protection is processed every 10 milliseconds. Internal status ZS-W is set when |0| < Phase shift 0 threshold and V0 > Voltage V0 threshold and 3I0 > Current 3I0 threshold for the time given by the parameter Time of check. Internal status ZS-
W is cleared when any of conditions above is not true and V0 is less than Lover threshold of voltage V0 from common parameters.
0 is measured between -i0 and v0 if active power P0 is positive. If active power P0 is negative, 0 is measured between i0 and v0. Thedirection of the active power P0 is evaluated every 1 second. Active power is considered as positive if its value is greater than 0.4%
of its range. Active power is considered as negative if its value is less than -0.4% of its range. If the value of active power is between -
0.4% and 0.4%, the sign of the active power remains unchanged.
Parameters
Main Parameters
Enabled YES/NO Enables/disables this protection.
Limits
Voltage V0 threshold 0 to VMAX V0 must be greater than this parameter in order to set ZS-W.
Current 3I0 threshold 0 to IMAX 3I0 must be greater than this parameter in order to set ZS-W.
Phase shift 0 threshold 0 to 180° |0| must be less than this parameter in order to set ZS-W.
Time of check 0 to 2.55 s
Step 0.01 s
Internal status ZS-W is set if all conditions are true for the time given by
this parameter.
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Earth Fault Protection – Connection of the Resistor
Description
This protection is processed every 10 milliseconds. When V0 is greater than Voltage V0 threshold and 3I0 is greater than Current 3I0
threshold, the average 3I01 of 3I0 from ¼Time to subst. gnd. resistor connection to ¾Time to subst. gnd. resistor connection is
calculated. After Time to subst. gnd. resistor connection elapses, the average 3I02 of 3I0 from ¼Duration of gnd. resistor connection
to ¾Duration of gnd. resistor connection is calculated. Internal status ZS-R is set if 3I 02 >= (3I01 + 3I0 rise after gnd. resistor
connection). Internal status ZS-R is cleared when any of conditions above is not true and V 0 is less than Lover threshold of voltage
V0 from common parameters.
Parameters
Main Parameters
Enabled YES/NO Enables/disables this protection.
Limits
Voltage V0 threshold 0 to VMAX V0 must be greater than this parameter in order to set ZS-R.
Current 3I0 threshold 0 to IMAX 3I0 must be greater than this parameter in order to set ZS-R.
Time to subst. gnd. resistor connection 0 to 2.55 s
Step 0.01 s
This parameter indicates when the resistor is connected.
Duration of gnd. resistor connection 0 to 2.55 s
Step 0.01 s
This parameter indicates for how long the resistor is connected.
3I0 rise after gnd. resistor connection 0 to IMAX This parameter determines the minimal raise of 3I0 after the resistor is
connected.
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Voltage Unbalance Protection
Description
Voltage unbalance is processed every 100 milliseconds. Pickup is set if (100 * (VMAX - VMIN) / VMAX) > Unbalance threshold and
VMAX > VMAX threshold, where VMIN is minimal value of line to line of phase voltage and VMAX is maximum value of line to line of phase
voltage. Trip is set when pick up is set for the time given by the Time of threshold. Pickup is cleared when any of conditions above is
not true. Trip is cleared when the pickup is not set for the time Time of threshold.
The protection opens the circuit breaker, when the trip is set. The open control of the circuit breaker is enabled if the value of the
parameter Open by protection is YES and the signals blocking open function are set to 0.
The trip can also be signalled by the relay output (see chapter Signalling by the Relay OutputSignalling by the Relay OutputSignalling
by the Relay Output). The address of the signal relay is defined by the parameter Address of trip signal relay.
The principle of the voltage unbalance function is shown in the following figures.
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Parameters
Main Parameters
Enabled YES/NO Enables/disables this protection.
Limits
Unbalance threshold 0 to 100 %
Step 1 %
This parameter defines unbalance threshold for the following equation:
(100 * (VMAX - VMIN) / VMAX) > Unbalance threshold
Time of threshold 0 to 25.5 s
Step 0.1 s
Trip is set when pick up is set for the time given by the Time of
threshold.
VMAX threshold 0 to VMAX The voltage unbalance protection is enabled when VMAX is greater than
this parameter.
Automatics
Open by protection YES/NO Enables/disables opening by this protection.
Signalling
Address of trip signal relay 0 to 19, none This parameter defines the address of the relay for signalling of trip.
Evaluated Inputs
Evaluate from voltage Phase
Line to line
Processed inputs are selected by this parameter.
Current Unbalance Protection
Description
Current unbalance is processed every 100 milliseconds. Current unbalance is blocked when trip of overcurrent protection is set.
Additionally current unbalance can be blocked when trip of earth fault protection is set. Blocking by earth fault protection trip has to
be enabled by parameter Blocking by signal of earth fault protection.
Pickup is set when one of following condition is true:
If IMAX is between Lower threshold of current IMAX and Upper threshold of current IMAX, the following condition is evaluated:
(100 * (IMAX - IMIN) / IMAX) > Unbalance threshold + ((100 - Unbalance threshold) * (Upper threshold of current IMAX - Imax)) / (Upper
threshold of current IMAX - Lower threshold of current IMAX))).
If IMAX is greater or equal to Upper threshold of current IMAX, the following condition is evaluated:
(100 * (IMAX - IMIN) / IMAX) > Unbalance threshold.
IMIN is minimal value of the current and IMAX is maximum value of the current. The value of the current is averaged over 100
milliseconds for current unbalance protection. The equations showed above are expressed in the following figure.
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Pickup of current unbalance is set when current unbalance ratio is over red line in the figure (the hatched area). Trip is set when pick
up is set for the time given by the Min. duration of threshold break. Pickup is cleared when condition above is not true. Trip is
cleared when the pickup is not set for the time Min. duration of threshold break.
The protection opens the circuit breaker, when the trip is set. The open control of the circuit breaker is enabled if the value of the
parameter Open by protection is YES and the signals blocking open function are set to 0.
The trip can also be signalled by the relay output (see chapter Signalling by the Relay OutputSignalling by the Relay OutputSignalling
by the Relay Output). The address of the signal relay is defined by the parameter Address of trip signal relay.
Parameters
Main Parameters
Enabled YES/NO Enables/disables this protection.
Limits
Upper threshold of current IMAX 0 to IMAX Upper threshold of current IMAX for current unbalance equation.
Lower threshold of current IMAX 0 to IMAX Lower threshold of current IMAX for current unbalance equation.
Unbalance threshold 0 to 100 %
Step 1 %
This parameter defines unbalance threshold for the following equation:
For Lower threshold of current IMAX ≤ IMAX ≤Lower threshold of current
IMAX: (100 * (IMAX - IMIN)/IMAX) > Unbalance threshold + ((100 - Unbalance
threshold) * (Upper threshold of current IMAX - Imax)) / (Upper
threshold of current IMAX - Lower threshold of current IMAX))).
For IMAX ≥ Upper threshold of current IMAX:
(100 * (IMAX – IMIN) / IMAX) > Unbalance threshold.
Min. duration of threshold break 0 to 25.5 s
Step 0.1 s
Trip is cleared when the pickup is not set for the time defined by this
parameter.
Blocking by signal of earth fault
protection
YES/NO Enables/disables current unbalance blocking if earth fault protection trip
is set.
Automatics
Open by protection YES/NO Enables/disables opening by this protection.
SignallingAddress of trip signal relay 0 to 19, none This parameter defines the address of the relay for signalling of trip.
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AutomaticsThe RTU7 unit provides two automatic functions: Automatic open after unsuccessful reclosing and automatic reclosing. Their
description follows.
Automatic Open after Unsuccessful Reclosing
Description
Automatic open after an unsuccessful reclosing is processed every 10 milliseconds. The automatic is waiting for an open after the
trip of the overcurrent/short circuit or earth fault protection occurs. The lines is considered as switched off if all currents are lessthan Dead line current threshold and all line to line voltages are less than Dead line voltage threshold for at least 40 milliseconds.
After that the automatic waits for the second trip. The lines have to be switched off after the second trip for at least Min. duration
of dead line. Otherwise the automatic do not open the circuit breaker.
The time between the first trip and the opening by the automatic has to be less than Max. time to open by short circuit or Max.
time to open by earth fault when the first trip was caused by the short circuit/overcurrent or by the earth fault, respectively. After
this time elapses a next trip is considered as the first one.
The open of the circuit breaker is enabled when the parameter Open after short circuit or Open after earth fault is YES if the circuit
was open by the short circuit/overcurrent or by the earth fault, respectively. The both parameters have to be set to YES if the first
open was caused by other source than the second one.
Parameters
Main Parameters
Enabled YES/NO Enables/disables this automatic.
Limits
Dead line voltage threshold 0 to VMAX The line is considered as switched off if all line to line voltages are less
than this parameter.
Dead line current threshold 0 to IMAX The line is considered as switched off if all phase voltages are less than
this parameter.
Automatics
Open after short circuit YES/NO Enables/disables opening by this automatic after the short
circuit/overcurrent.
Open after earth fault YES/NO Enables/disables opening by this automatic after the earth fault.
Max. time to open by short circuit 0 to 255 s
Step 1 s
The maximum time between the first trip by the short
circuit/overcurrent and the opening by the automatic. The current cycle
of the automatic is finished after this time elapses.
Max. time to open by earth fault 0 to 255 s
Step 1 s
The maximum time between the first trip by the earth fault and the
opening by the automatic. The current cycle of the automatic is finished
after this time elapses.
Min. duration of dead line 0 to 2.55 s
Step 0.01 s
The circuit is opened after this time.
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Automatic Reclosing
Description
Automatic reclosing (AR) is processed every 10 milliseconds. When the overcurrent/short circuit or earth fault protection opens, the
automatic reclosing tries to close after the time defined by the parameter Time to xth
reclosing. The parameters set of each
protection contains the parameter which defines maximum number of the AR cycles (0 disables AR) after open by the protection.
When the maximum number of the AR cycles is reached, no additional AR is performed and line stays off. The automatic reclosing is
to be enabled by the parameter Enabled and by the signal.
The reclosing mode is selected by the parameter Reclosing mode. Description of three available modes follows.
1.
Standard
In this mode any of protection can open the switch gear. It is not important which protection caused open. The maximum
number of the AR cycles is given by the minimum of maximum numbers of the AR cycles of all protections that caused open.
2.
Fast+slow
Only two cycles (fast – 1st
time and slow – 2nd
time) are used in this mode. The VDOs/VDIs are used for selection of used
cycles. It is not important which protection caused open.
3.
Fast+slow limited
Only two cycles (fast and slow) are used in this mode. The fast (1st
time) cycle is used for the earth protection and the slow
(2nd
time) cycle is used for all protections. The VDOs/VDIs are used for selection of used cycles.
The current reclosing cycle is cancelled by manual or remote control of the switch gear. The automatic reclosing is disabled after its
cancellation (manual or remote control of the switch gear) for the time given by the parameter Reclos. blockade duration after
close by op. Running reclosing cycle is cancelled also if the switch gear is closed for the time given by the parameter Time for
cancellation of running reclosing. The automatic reclosing closes the switch gear if only the current switch gear status is open or
indefinite and the value of current in all three phases is less than Dead line current threshold. Otherwise the current reclosing cycle
is cancelled. The time between the open and the close is given by the parameters Time to first reclosing to Next cycle of reclosing.
It is possible to define up to six different times that typically extend. The Time to first reclosing is used for the first reclosing cycle,
the Time to second reclosing is used for the second reclosing cycle, and so on.
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Parameters
Main Parameters
Enabled YES/NO Enables/disables this automatic.
Limits
Dead line current threshold 0 to IMAX The line is considered switched off if all phase currents are less than this
parameter.
Automatics
Time to first reclosing 0 to 25.5 s
Step 0.1 s
The time between the open and the automatic reclose for the first cycle.
Time to second reclosing 0 to 255 s
Step 1 s
The time between the open and the automatic reclose for the second
cycle.
Time to third reclosing 0 to 255 s
Step 1 s
The time between the open and the automatic reclose for the third
cycle.
Time to fourth reclosing 0 to 255 s
Step 1 s
The time between the open and the automatic reclose for the fourth
cycle.
Time to fifth reclosing 0 to 255 s
Step 1 s
The time between the open and the automatic reclose for the fifth cycle.
Next cycle of reclosing 0 to 255 s
Step 1 s
The time between the open and the automatic reclose for the sixth and
next cycle.
Reclos. blockade duration after close
by op
0 to 255 s
Step 1 s
The automatic reclosing is disabled after its cancellation (due to the
remote or manual control) for the time given by this parameter.
Time for cancellation of running
reclosing
0 to 255 s
Step 1 s
Running reclosing cycle is cancelled if the switch gear is closed for the
time given by this parameter.
Reclosing mode Standard
Fast+slow
Fast+slow
limited
Standard – the maximum number of automatic reclosing cycles is given
by the parameter in each protection.
Fast+slow – two cycles (fast – 1st
time and slow – 2nd
time) are used. The
VDOs/VDIs are used for selection of used cycles.
Fast+slow limited – two cycles (fast – 1st
time and slow – 2nd
time) are
used. The fast cycle is used for the earth protection and the slow (2
nd
time) cycle is used for all protections. The VDOs/VDIs are used for
selection of used cycles
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Fault Records
Common Settings
Description
Six analogue channels (v1, v2, v3, i1, i2, i3) and sixteen digital channels (its source is selectable by the parameter Source) are recorded
every 1 millisecond. The records are saved to the mass memory when the digital channel, whose parameter Record starting is set to
YES, changes its state from 0 to 1. The length of the record is between the Min. total record duration and the Max. total duration of
one record. The record is recorded if its length is less than Max. total duration of one record and at least one digital channel, whose
parameter Record holding is set to YES, has state 1. A record can be started by the ON remote control of the special signal also. The
record started this way has length approximately 150 milliseconds. All records can be deleted by the ON remote control of the
special signal.
Records are transmitted to the control system automatically (has to be enabled by the parameter Automatic transfer of records) or
on the user request. If the parameter Delete record after transfer is set to YES, the successfully transmitted record is deleted from
the memory. This parameter should have value NO if the parameter Circular rewriting has value YES.
The parameter Circular rewriting enables circular rewriting of the oldest records if there is no free space for a newer one.
Parameters
Main parameters
Enabled YES/NO Enables/disables creation of the fault records.
Channel 0 Channel of the fault recorder (only 0 is allowed).
Station name text Name of the station with length up to 64 characters.
Fault Records Settings
Min. total record duration 0.2 to 25.5 s
Step 0.1 s
Determines minimal length of one record.
Max. total duration of one record 0.2 to 25.5 s
Step 0.1 s
Determines maximum length of one record.
Automatic transfer of records YES/NO Enables/disables automatic transmission of the record to the control
system.
Circular rewriting YES/NO Enables/disables circular rewriting of the records.
Delete record after transfer YES/NO Enables/disables automatic deletion of the record after its transfer to the
control system.
Voltage Conversion
Primary range Primary range of the voltage (depends on used input module and sensor).
Secondary range Secondary range of the voltage (depends on used input module).
Unit V, kV, … Unit of the voltage.
Current Conversion
Primary range Primary range of the voltage (depends on used input module and sensor).
Secondary range Secondary range of the voltage (depends on used input module).
Unit mA, A, … Unit of the current.
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Analogue Channels
Description
Fault record contains six analogue channels (i1, i2, i3, v1, v2, v3 in the REC format) or eight analogue channels (i1, i2, i3, i0, v1, v2, v3, v0 in
the COMTRADE format). The RTU Behaviour Viewer application supports both formats. In both cases are available all channels
because the application RTU Behaviour Viewer computes the missing channels.
The parameter Channel name is available and contains channel identifier of the channel for the COMTRADE format.
Parameters
Main parameters
Channel name Text Analogue channel identifier with length up to 30 characters.
Digital Channels
Description
Fault record contains sixteen digital channels. The source of all channels is selectable by the parameter Source. The source can be a
digital input, output, internal status, etc. State of the channel is the same as the state of its source if the parameter Negation has
value NO. Otherwise it has opposite value than its source. The digital channel starts a new record if its value changes from 0 to 1 and
its parameter Record starting is YES. The digital channel keeps recording in progress to the maximum length of the record given by
the parameter Max. total duration of one record if its value is 1 and its parameter Record holding is YES.
The parameter Channel name is available and contains channel identifier of the channel for the COMTRADE format.
Parameters
Main parameters
Channel name text Digital channel identifier with length up to 30 characters.
Fault Records Settings
Record starting YES/NO Enables/disables start of recording by the change of this channel to 1.
Record holding YES/NO Enables/disables holding of the record to the Max. total duration of one
record if the value of this channel is 1.
Source DI, VDI, … Determines the source of the channel. The source can be a digital input,
output, internal status, etc.
Negation YES/NO Enables/disables negation of the channel.
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SignallingThe signalling panel can be connected to the RTU7 unit. The meaning of each signalling LED is configurable in the expressions.
Internal statuses are available in the expressions and expose for example internal states of protections. Internal statuses can be
used as a source of digital channels in the fault records. A list of internal statuses follows.
Address Description
0 One second tick
1 HioCom2 communication status
2 Reserved3 Supply voltage lost
4
Voltage „A“
DC power supply: active when DI02 is active
AC power supply: active when power supply voltage is grater then 23% of its range
5
Voltage „B“
Active when US >= 50 % of US range.
Flashing 1 Hz when US >= 5 % of US range. Otherwise it is inactive. US is the average of the line to line voltages V12, V13,
V23.
6 Breaker status (double bit)
7 Breaker status – open
8 Breaker status – close
9 Reclosing active
10 Reclosing finished
11 ZS-W
12 ZS-K
13 ZS-I
14 ZS-R
15 ZS-V0
16 Active power is less than zero (-P)
17 ZSW-0 (|0| < Phase shift 0 threshold)
18 Open after reclose
19 Reclosing – close