Danfoss Performer Compressor SZ185

[Unreal688]

Hi all

I've been working on a carrier chiller with the above compressor. The chiller has alarmed a couple of time on incorrect compressor phase rotation. Now I'm sure that it can only pick this up through the transducers reading the same pressure over a period of time. But the transducers are reading correctly, but i have noticed that when the 24v signal is sent to the compressor to run it takes a good couple of minutes before the comp actually starts. It has a motor protector on it which receives the 24v signal which then sends the 24v up to the contractor if the internal klixon is reading ok. This is the process thats taking its time so i think its probably the motor protector. All i wanted to know is that when i took the resistance of the klixon it was reading 288ohms and the comp temp was about 5-10 degrees C. Is this normal because it doesn't tell you what the klixon should read on the danfoss website

Thank you
Unreal

[chemi-cool]

Is there any timer set to protect the compressor from short cycle?

[james10]

Chiller model please, all transducers do is read pressure

[Grizzly]

Hi unreal688.

Code 16 on the attached refers to the SCPM.
James will likely know as he seems quite clued up on these?
I would suspect the protection Module.
Grizzly

Attachment 8659

[Unreal688]

Nothing to do with a timer because the controller is asking for the comp to fire up and the signal is been sent out. I know all the tranducers do is read pressure but the system looks at these pressures and if the suction and discharge are reading the same it throws the reverse rotation fault up. i know this because the transducers were changed by carrier 2 years ago for the same fault. but this time the transducers are ok chiller model: 30RH-100-B0448

[james10]

Hi unreal688.

Code 16 on the attached refers to the SCPM.
James will likely know as he seems quite clued up on these?
I would suspect the protection Module.
Grizzly

Attachment 8659

That alarm list appears to be from a screw machine IE 30Gx - SCPM = screw compressor protection module the 30rh uses scroll compressors, hope this helps

[james10]

Try operating the compressor in quick test mode and check you have good continuity through your wiring and your contactor, also check your fans in quick test mode if all is correct you need to check your hp switch
Do you have the soft start option fitted?

[Unreal688]

Its ok i was right. it was the motor protector. Picked one up on friday, fitted it. no more reverse rotation alarm.
The system goes out on this alarm if the comp has no power to it. which in my case it didn't because the motor protecter relay wasn't switching to send the 24v up to A1 on the contacter. it took about 3-4 mins before it would switch and start running.

[Grizzly]

Good news!
Thanks for keeping us all informed.
Grizzly