Unisab II external 4-20mA signal, documentation needed.

[Josip]

Hi, petter78

Hi all,
I rewired an Unisab II yesterday, it had two 4-20mA signals in, one in 33, 34 and one in 47, 48 i believe.
I needed to control the set point on the water, that worked well in 47, 48.
What is the other input for?
It was setup for weather compensation, but I changed that to external setpoint. The input in 47, 48 was a temp transducer in the pipe up the building. There are two chillers and a buffer tank.

Does anybody have a manual and a wiring diagram on the unisab II?

Regards,
Peter

I was asking my friend electrician for assistance .... and he told me this ....

32 - +24V
33 - GND
34 - 4-20mA
are terminals for analog input for Volume slide position or outdoor temp compensation


47-48 terminals are DI (digital input) start request feedback - if use remove jumper


To control brine temperature there are terminals 25-26-27-28 for analog input of brine temperature from temperature sensor PT100 with scale -50C/+180C with 4 wires ...need to remove 100 Ohm resistor -capacity control must be set to .... CONTROL on BRINE ...

or to use terminals for universal regulator (External input)
37 - +24V
38 - GND
39 - 4-20mA signal

and then make a calibration according to regulator used

you can read about all above in the manual under compressor regulation chapter 6 received from HVACRsaurus


Hope this will help a little ...

Best regards, Josip