Not for the company...for the tech!
Don't see many of these around here. Got a Mcquay centrifugal, Model PEH087-AAAB, ser#57B81025-00 Style: 9641925010 Appears to be 200 series panel. Trouble with the unit was that it was in alarm, that alarm being "no 5volt DC signal to Sensor #19" Long story short, the Analog input was not seeing 5 volts DC. I pulled and checked the connector at the analog input, pressing in the wire harness and even replaced the connector and was able to get the machine online and it would run for 20, 30 minutes or so and i watched the signal drop to 4.5 volts and it kicked out, same fault. I assume something is dragging it down.
Couple of questions: first, Why is Sensor 19 listed as the Transducer Power Voltage Ratio? Is sensor 19 just an actual input status? All transducers are feeding back, I just seem to be dragging the power signal down.
I am lucky enough to have another machine onsite and am probably going to try to swap out the MCB to beggin with. i did monitor this other unit and noted that it had a steady 4.9 vdc signal. Any input on testing these modules? thanks in advance.