PID Temp control

hounddog

Member

H

Join Date

Jun 2003

Posts

79

• Jun 25, 2003

• #1

Could someone explain how to use a Analog//Digital option card with a omron plc to control a I/P controlled valve, such as a steam valve.

The temperature is controlled by how much pressure tranducer senses the presser is.

 

BobB

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Jun 2002

Location

Sydney

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• Jun 25, 2003

• #2

The best option is to use and anologue input from an RTD or themocouple, an analgue output to drive the proportional valve with 4-20ma or 1-5volts and the PID function. Just set the value of the temperature that you want and put the PID function into "auto tune". It will do it all for you.
beerchug

 

barry.fletcher

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B

Join Date

Jun 2003

Posts

3

• Jun 27, 2003

• #3

Is the temperature the variable that you are trying to control via pressure if so have you considered cascading the two loops, its a very simple operation but we would require a bit more info.
Regards

 

rock

Member

R

Join Date

Aug 2003

Posts

35

• Aug 27, 2003

• #4

hot water control for temperature

actually want to control a valve that would open to allow hot steam or water to flow through a heat coil, as the desired temp is reached the valve be closed off just enough to maintain the desired temperature or open just enough to allow just enough steam or hot water to flow if needed to increase the temperature

 

BobB

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Jun 2002

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Sydney

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• Aug 27, 2003

• #5

Refer to my previous answer. If you are using the CS1 or CJ1 they have an autotune bit you can turn on for the PID function. When tuning is complete, the bit turns off. Could not be easier.
beerchug

 

rsdoran

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Apr 2002

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Birmingham, AL

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7,371

• Aug 27, 2003

• #6

I have got to use Omron

I must learn Omron