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View Full Version : johnson controls OWS overrides?



smarco
03-14-2007, 10:43 AM
We have installed a DX-9100 on an existing N2 bus that is connected to a jci OWS with I believe one NCM. The DX is controlling three cooling tower fans on VSDs with wetbulb reset. We are using the Line Segment Function to create the reset schedule with the output of that being the condensor water temp setpoint. My question is does anyone know if the resultant output of the Line Segment Function can be overridden from the OWS front end without causing any hiccups in the system. The output feeds a PID module which in turn sends the appropriate signal to an AO that drives the VSDs. We have been told that calculated values such as the Line Segment output cannot be mapped to the front end. Any insight would be greatly appreciated.

controlgeek
03-14-2007, 12:55 PM
The output of the segment can be mapped. I'm not sure if it is direct mappable now but in the past it would have been mapped through a CS Object.

cmakowk
03-14-2007, 08:14 PM
I agree...Map it in a CS Object and I would not let it be adjusted
in CS Object but only overridden. This way it doesn't stay adjusted
and someone forgets about it. With SWO next to CS Object will be
a flag that something is overridden.

smarco
03-16-2007, 10:16 AM
thanks for the info....I went ahead and reviewed the jci docs on the CS object and it does indicate that we should be able to accomplish what is necessary using the CS Object.

Thanks again!