7/27/2019 18427996 Motor Starter Solutions 3

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General 1 TeSys motor starters 1Levels of service

Type 1 and type 2 coordination according to the standardThe standard defines tests at different levels of current; the purpose of these tests is

to place the equipment in extreme conditions.The standard defines 2 types of coordination, according to the condition of the

components after testing:

type 1,

type 2.

To determine the type of coordination, the standard requires that the behaviour of the

equipment be tested under overload and short-circuit conditions for 3 fault current

values, covering overload and short-circuit conditions.

Type 1 coordination

Type 1 coordination requires that in a short-circuit condition, the contactor or starter

must not present any danger to personnel or installations and must not be able to

resume operation without repair or the replacement of parts.

1 Thermal overload relay curve.2 Fuse.

3 Tripping of thermal overload relay only.

4 Thermal limit of the circuit-breaker.

5 Thermal overload relay limit.

6 Current broken by the SCPD (1).

7 Circuit breaker magnetic trip.

Type 2 coordination

Type 2 coordination requires that In a short-circuit condition, the contactor or s tartermust not present any danger to personnel or installations and must subsequently

be able to resume operation. The risk of contact welding is permissible; in this case,

the manufacturer must indicate measures to be taken regarding maintenance of the

equipment.

Type 2 coordination increases reliability of operation.

Current valuesCurrent Ico (overload I < 10 In)

The thermal overload relay associated with the contactor provides protection against

this type of fault, up to a value Ico (see curve) defined by the manufacturer.

Standard IEC 60947-4-1 specifies the 2 current values to be used for checking

coordination between the thermal overload relay and the short-circuit protection

device:b at 0.75 Ico only the thermal overload relay must trip,

b at 1.25 Ico the short-circuit protection device must operate.

Current r (low level short-circuit 10 < I < 50 In)

The main cause of this type of fault is the deterioration of insulating materials.

Standard IEC 60947-4-1 defines an intermediate short-circuit current r. This test

current makes it possible to check whether the protection device is providing

protection against low-level short-circuits.

Operational current Ie (AC-3) (A) Current r (kA)

Ie y16 1

16 < Ie y63 363 < Ie y125 5125 < Ie y315 10

315 < Ie y630 18

630 < Ie y1000 30

Current Iq (short-circuit > current r)

This type of fault corresponds to a dead short and is relatively rare. It can be caused

by a connection error during maintenance work. Short-circuit protection is provided

by fast operating devices.

Standard IEC 60947-4-1 defines a current Iq. The coordination tables supplied by

Schneider Electric are based on a current Iq that is generally u 50 kA.

(1) SCPD: short-circuit protection device.

1 10 50

In

t

0,75 Ico 1,25 Ico

Ico

Ir Iq

1

3 6

7

4

5

2

ak In

Overload zone Short-circuit zoneLow-levelshort-circuit zone