pct40

7/27/2019 pct40

http://slidepdf.com/reader/full/pct40 1/8

<EXTENDED> WARRANTY

2 years

The Armeld PCT40 system provides a

cost-eective way o teaching a wide

range o process control techniques

in a simple basic unit. More advanced

aspects o process control can be

addressed by adding optional extras

to the basic system.

PCT40 o it optio Poc ccoy -PCT41Capabilities

> The basic PCT40 is used under computer control to

demonstrate a variety o single control loops. It can be quickly

recongured between processes, such as level control,temperature control, fow control and pressure control.

The advanced sotware allows the student to change the

control parameters, record results and analyse the results or

the dierent congurations

> The PCT41 expands on the capabilities o the PCT40, and

oers a wider range o control loops and strategies, including

remote set points, dual loops, fuid property control (using

conductivity). Again all these are under sotware control

> Other accessories are available, including a control console

with commercial PID controller, plus a pH probe and a

pneumatic valve or those wishing to implement specialised demonstrations

> Large range o demonstrations rom straightorward hardware

> Computer control as standard

> Computer generated loop disturbances or repeatability,

allowing small variations in control parameters to

be investigated

> Flexible system, suitable or project work

issue 4The latest version of this data sheet is available at:

www.armfield.co.uk/pct40

Multifunction Process control teaching systeM – PCT40

Pct series: Process control technology

7/27/2019 pct40


PCT40 Outflow control using an on/off controller (Pressure sensor to solenoid valve)

Direct heating/batch operation using a PID controller (Temperature sensor to heater power control via solid state relay)

PCT40 Basic Process Control System

The PCT40 contains everything that is needed to

perorm a range o single-loop process control

experiments in conjunction with a PC.

It includes a variable volume process tank, a

hot water tank with electric heater and indirect

heating/cooling coil, a hot water pump, two non-

dedicated pumps, three on/o solenoid valves

and a proportioning valve. The instrumentation

includes temperature sensors, two dierential

water pressure sensors, a mechanical level

sensor (foat switch) and an electronic level

sensor (conductivity). The inlets and outlets o the various pumps, valves and tanks incorporate

sel-sealing quick release ttings. This allows the

conguration to be quickly changed, oering a

wide variety o dierent loops.

The PCT40 includes a computer interace (USB),

and all o the parameters can be controlled

directly rom the computer, i.e. the pump speeds,

the valve positions and the heater power. The

computer also displays the readings rom the

various measurement sensors.

The sotware supplied with the unit includeson/o, time proportioned and proportional/

integral/derivative (PID) algorithms where all the

parameters are easily accessed and adjusted by

the user. This approach means that a separate

electronic console is unnecessary or most

applications.

The fexible nature o the system also allows or

a wide variety o dierent disturbances to be

applied to the loops to allow the eectiveness o

the control parameters to be compared. As all

these disturbances are under sotware control,

they can be repeated precisely during the

optimisation process, thus allowing an excellent

degree o ne-tuning to be implemented.

A pressure regulating valve with lter is also

included to isolate the equipment rom fuctuations in the water supply pressure.

The type o loops achievable with the basic

PCT40 include:

> Tank water level by varying input fow

> Water fowrate by varying pump speed

> Temperature o water in a vessel

by varying the heater power

> Temperature o water heated

indirectly by varying the fowrate

(All these loops are under sotware control)

DesCription

Cold water

Disturbance

SOL2

P1

PSV PRV

SOL3 TYPICAL LEVEL

CONTROL LOOP

on/off

control

Heater

Cold water

Disturbance

Coil

SSR

T1T3

T2 PSV PRV

PID

control

TYPICAL TEMPERATURE

CONTROL LOOP

7/27/2019 pct40


PCT41

PCT41 Process Vessel Accessory

The PCT41 extends the capability o the basicPCT40 by adding an additional process vessel,

complete with a heating/cooling coil and a stirrer.

Again the inputs and outputs incorporate quick

release ttings.

The PCT41 also includes a conductivity probe to

allow cost eective fuid property demonstrations

to be perormed.

The addition o the process vessel allows

more complex process control problems

to be addressed, including remote set point

demonstrations. Again these all take place withthe repeatability advantages that electronic and

sotware control brings.

Additional loops that can be implemented with

the PCT41 include:

Single loops in combination:

> Conductivity control o reactor contents

by varying fowrate o one component

> Temperature control o reactor contents

by varying heating fuid fowrate

> Temperature control o heating fuid by varying heater power Remote setpoint control:

> Ratio control o two fows (Fig 1)

> Cascade control o conductivity and

fow (Fig 2)

> Feedorward control o fow to fow

> Feedorward control o fow combined

with eedback control o conductivity

(All these loops are under sotware control)

PCT42 pH Sensor Accessory

The PCT41 includes a conductivity probe as part o the basic supply. This conductivity probe can

be used to demonstrate fuid property control

systems, without the maintenance problems which

can be experienced with pH probes. However, as

pH control is probably the most common industrial

application o this type o control system, users

may wish to implement true pH control loops. This

can easily be implemented by adding the PCT42

pH sensor accessory to the combined PCT40 +

PCT41 system.

RSP

FEED A FEED B

RATIO CONTROL USING

REMOTE SET POINT CONTROLLER

PID

controller

DP1

PUMP

A

PUMP

B

DP2

IN

IN

OUT

OUT

Conductivity sensor

C

RSP

controller FEED A FEED B

CASCADE CONTROL OF

CONDUCTIVITY AND FLOW

USING REMOTE SET POINT CONTROLLER

PUMP

A

PUMP

B

DP2

RSP

RSP

controller IN

OUT

PID

controller

IN

OUT

Conductivity sensor

C

Fig 1: Fig 2:

7/27/2019 pct40


PCT44PCT43

PCT43 Electronic Console

The PCT43 is an electronic console that can be

used to control the PCT40 (+PCT41/42) instead o

a computer. It includes controls or the pumps,

valves and heater, plus a display or the sensors.

It incorporates a commercial PID controller,

complete with RS232 interace. Other acilities

include 4-20mA interaces and selector switches

to allow many o the dierent congurations to

be implemented without using external jumper

connections.

The PCT43 allows all o the PCT40 and PCT41

single loop congurations to be implemented without using a computer. Using this console also

allows the sensor data to be logged and displayed

on a computer (using the PCT40 USB interace),

but with the control unctions being implemented

in the PCT43 hardware, rather than the computer

sotware.

Facilities include:

> Use o a commercial PID controller

> Simple interacing to other PLC and/or

PID controllers

> Use o 4-20mA interaces

> Use o serial communications

(RS232) in a control system

> Simple SCADA demonstration (requires PC)

PCT44 Pneumatic Valve Module Accessory

The PCT44 is a pneumatic control valve, plus

associated components, or use with the PCT40/41

system. Retaining the fexible concept o the

whole range, it can be plumbed into many o the

fow control loops, and provides a good illustration

o pneumatic valve technology.

Note: This accessory requires a compressed air supply

software Capability

The system is supplied with a complete educational

sotware package with a wide range o acilities and unctions. For most applications the computer

is the primary interace between the user and the

equipment.

The sotware displays real time process mimic

diagrams, with readings o the relevant sensor

outputs, and controls or the system inputs. The on/

o, time proportioned and PID control algorithms

are accessible through ‘pop-up’ control boxes,

which give the user access to all the key control

parameters, including the proportional band, the

integral time and the derivative eect.The sotware is supplied with detailed mimic

diagrams, and ull instructional help texts or ten

predetermined student exercises when using

PCT40 and an additional our exercises when

using PCT41. These predetermined strategies

have been careully chosen to illustrate a wide

range o the system capability and possible

control strategies, i.e. level, fow, temperature,

pressure, fuid characteristics, single PID

loops, cascade and multiple loops, remote set

points, etc. However, because o the fexibility

o the system, many more control situations

are congurable than it is possible to provide

predened student exercises or. Because o this,

Armeld have included a user congurable option

with the sotware, which allows the ull range o

capability rom the system to be explored. This is

particularly useul or student project work.

Whichever conguration is being used, the

sotware provides powerul data logging and

graph plotting acilities, together with sensor

calibrations and a wide variety o display and

data export options.

The computer communicates to the PCT40 using

a standard universal serial bus (USB) interace.

7/27/2019 pct40


Equipment Selection Computer control Hardware control

Single loop Multi-loop Remote

set point

Single loop

Level PCT40 PCT40 + 43

Flow PCT40 PCT40 + 43

Temperature PCT40 PCT40 + 43

Pressure (basic) PCT40 PCT40 + 43Pressure

(using Pneumatic control valve)

PCT40 + 44 PCT40 + 43 + 44

Fluid Property

(conductivity)

PCT40 + 41 PCT40 + 41 PCT40 + 41 PCT40 + 41 + 43

Fluid Property

(pH)

PCT40 + 41 + 42 PCT40 + 41 + 42 PCT40 + 41 + 42 PCT40 + 41 + 42 + 43

FOr FurTher InFOrmaTIOn On The aDvanCeD FeaTures OF

The sOPhIsTICaTeD armFIelD sOFTware vIsIT:.fd.co.k/ot_dtt.t

When used with the PCT43, the sotware also

provides a simple SCADA demonstration. The

process is controlled using the PID controller

in the PCT43, but the P, I & D values can be

accessed and varied by the computer, using the

RS232 interace. At the same time the status o

the process can be displayed on the computer by

using the USB interace or data logging only.

Universal Software Interface

For users who wish to write their own sotware,

e.g. in Matlab or LabView, ull instructions are

given or communications with the PCT40 via its

built in USB interace. Advanced users are also

given the acility to include their own process

control algorithm, written in a suitable language

such as C++. This is useul or exploring advanced

and non-linear control systems.

CoMpUter reQUireMent

The system is designed to be used with a

personal computer (not supplied). The computer

must have a USB connection available, and run

Windows 98 or above.

7/27/2019 pct40


PCPLC CONTROLLER PCT19BR

MULTIFUNCTION PROCESS CONTROLTEACHING SYSTEM PCT40

pCt42: H s acc

eQUipMent reQUireMents

Requires: PCT40 and PCT41

oVerall DiMensions

Height: 0.12m

Width: 0.012m

Depth: 0.012m

sHippinG DiMensions

Volume: 0.01m³

Gross weight: 3kg

PCT43: Electronic Console


Requires: PCT40

oVerall DiMensions

Height: 0.275m

Width: 0.365m

Depth: 0.27m

sHippinG DiMensions

Volume: 0.1m³

Gross weight: 15kg

PCT40: Basic Process Control System


Requires:

Personal computer or PCT43

Cold water supply (1.5 l/min at 2 Bar gauge)

Single-phase electrical supply (see below)

Order Codes:

PCT40-A: 220-240V, 50Hz

PCT40-B: 110-120V, 60Hz

PCT40-G: 220V, 60Hz

oVerall DiMensions

Height: 0.7m

Width: 1.0m

Depth: 0.54m

sHippinG DiMensions

Volume: 0.4m³

Gross weight: 40kg

PCT41: Process Vessel Accessory eQUipMent reQUireMents

Requires: PCT40

oVerall DiMensions

Height: 0.45m

Width: 0.25m

Depth: 0.3m

sHippinG DiMensions

Volume: 0.1m³

Gross weight: 20kg

7/27/2019 pct40


PNEUMATIC VALVEMODULE ACCESSORY PCT44

CONSOLE PCT43

PROCESS VESSELACCESSORY PCT41

ph SENSOR ACCESSORY PCT42

PID CONTROLLER PCT20H

PCT44: Pneumatic Valve Module Accessory


Requires: PCT40

(Also requires a clean supply o compressed air

at a pressure o at least 21 psig)

oVerall DiMensions

Height: 0.4m

Width: 0.35m

Depth: 0.35m

sHippinG DiMensions

Volume: 0.1m³

Gross weight: 26kg

It is possible to control the PCT40/41 loops using

external PLC devices or PID controllers. These can be connected directly to the PCT40 or specic

congurations, however, with the PCT43 electronic

console it becomes very easy to connect up the

inputs and outputs to enable a range o loops to be

demonstrated.

Armeld oer two external units in addition to the

PCT43 that can be used or this purpose:

PCT19BR

The PCT19BR is an example o a typical industrial

PLC that can be ound in many large scale process

control applications. It is based on the Allen Bradley

SLC500, and includes the Allen Bradley AI ladder

logic programming sotware.

PCT20H

The PCT20H is an example o a typical industrial

PID controller that can be ound in many large

scale process control applications. The controller

includes an RS485 interace and RS232 to RS485

converter that allows connection directly to a PC

with serial interace.

ALSO CONSIDER

PCT23MkIIThe PCT23MkII is a benchtop process plant trainer

used extensively in under-graduate engineering

education and or training plant supervisors and

operators.

It uses an industrial HTST pasteurisation plant to

demonstrate a complete range o process control

methods and strategies as used in industry.

The trainer incorporates an industrial style three

stage plate heat exchanger with chevron plates or

increased turbulence and eciency. A conductivity

sensor allows concentration measurement.

T copt PCT yt. Copt ot pt o ppy

anCillary eQUipMent

7/27/2019 pct40


orDerinG speCifiCation

• A multi-function process control teaching

system, capable o demonstrating level, fow, pressure and temperature control loops

• Desk top mounted and includes a built in

USB computer interace

• Options include: reactor vessel with

conductivity measurement, pH measurement, pneumatic control valve and

electronic console

• Includes the following process control

demonstrations:

Process principles

n Calibration o sensors (via PC sotware)

n Infow control

n Outfow control

nDirect heating

n Indirect Heating

n Batch operation

n Continuous operation

n Eect o sensor lag

(e.g. thermometer pocket)

n Eect o system time constant

(e.g. volume change)

n Eect o dead time (e.g. holding tube)

n Eect o mixing/stirring (requires PCT41)

Measured variablesn Level - on/o switch (xed hysteresis)

n Level - dierential on/o switch

(adjustable hysteresis)

n Level - proportional pressure sensor

(slow system response)

n Flow - Proportional turbine sensor

n Temperature - on/o switch (xed hysteresis)

n Temperature - proportional thermocouple sensors

n Static pressure - proportional

sensor (ast system response)

n Dierential pressure - proportional pressure (ast system response)

n pH - proportional sensor

(requires PCT41 and PCT42)

Controller types

n Manual control

n Eect o reverse/direct action

n On/o output with hysteresis

nTime proportioned output with adjustable P, I & D terms and

cycle time

n PID proportional output with

adjustable P, I & D terms

n Remote set point control (requires PCT41)

n Ratio, cascade and eedorward with

eedback loops (requires PCT41)

Controlled variables

n On/o fow control via solenoid valves

n Time proportioned fow control via solenoid valvesn Proportional fow control via pump speed

n Proportional fow control via

electrical proportioning valve

n Proportional fow control via pneumatic

proportioning valve (requires PCT44)

n On/o heater power control via solid state relay

n Time proportioned heater power

control via solid state relay

n Proportional heater power control

via solid state relay

© 2008 amfie d ltd. a rig hts reseved We reserve the right to amend these specifications without prior notice.E&OE

0209/3k/SO2452

learn more!

An ISO 9001 Company

Innovators in Engineering Teaching Equipment

<EXTENDED> WARRANTY

2 years

Head Office: Armfld LmtdBrdg Ho, Wt strt,

Rngwood, Hamphr.BH24 1DY england

Tlphon: +44 1425 478781Fax: +44 1425 470916e-mal: [email protected]

U.S. Office: Armfld inc.436 Wt Commodor Blvd (#2)

Jackon, NJ 0852 7Tlphon: (732) 928 3332Fax: (732) 928 3542e-mal: [email protected] you dispose of this data sheet

please recycle it.

Sourced from fully sustainable forestsISO14001/TCFCertied

pct40

Documents

Transcript of pct40