Editing Knowledge Base:Heating

Simple Heating Setup
by Mick Martin | Feb 28, 2012 | Knowledge Base

The client requested the following functionality,

Thermistor input to produce a 0-10 volt output to control a heating valve over a 4 degree centigrade band with the set point adjustable in software.
Thermistor input to give a relay output with a set point adjustable in software.
Input from others via software to give relay output for system on/off.
Input from others via software to give 0-10 volt output to vary fan speed.
Digital input to give a common fault signal to be sent via software to others.
A BAS Remote controller from Contemporary Controls was specified and the inputs and outputs defined as follows,

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SP1, SP2, Fan, Damper and Fault are all ModBus register addresses acces by a Trend Supervisor.

The follow diagram shows the logic strategy developed for the controller.

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The control was wired in to a distribution unit and wall mounted in the plant room.