SCC-300-HPC

[integrationx]

A question for anyone familiar with Circon products.

I have been asked to supply a controller to control a standard heat pump (2 compressors, reversing valve, etc). The catch is the consultant wants it to control based on the average of two zone sensors. He also wants two afterhours pushbuttons.

Can I connect the sensors individual and have the controller perform the average calculation without having to use a programmable controller?

[the_dude]

Yes, I think there might be...I have heard of people doing some funky wiring on a single input providing an "average" value. I would contact Circon T.S. to confirm or deny....

[jamcontrol]

I've seen where you can parallel 2 room sensor to get the average into one input. ACI thermistor sensors were used and it was some sort of resistor bridge they developed.

Since you want individual inputs for each, I think you'll need a programmable controller, SCC-300-PRG.

[sysint]

Although it would be a nice idea the SCC's don't have anything for averaging 2 separate inputs to the controller unless you go programmable.

You would need to do it similar to other manufacturers methods with one input. Override buttons could be done too. The SCC also has the ability to customize the curve for sensors.

[luckybob]

That is correct, you would need a programmable controller as this controller does not support what you need, although an easy way would be to take (2) 1K RTD sensors install at each location in series then wire each pair back to the AI in parallel.

[integrationx]

What are the options with the 'side loop'?

Can you add another temperature sensor, use the side loop to average it with the 'main' temperature sensor then send the result to the nviSpaceTemp?

[sysint]

No.

Side loop is either a scheduled/PI/2 position selection based on a setpoint. The effective setpoint can be bound but it won't help you with what you want to do.

[jamcontrol]

Check out the sample SCC programs supplied with their plug-ins. It might be quite easy to add the 2nd sensor input to the program. I think their located in Program files/circon/... somewhere there abouts.