Originally Posted by
hurtinhvac
Wondering how I'd troubleshoot this motor that occasionally doesn't want to start, what I should be seeing in the way of DC voltage as more speed is called for and how they basically work in conjunction with the board. Didn't find much useful info after an hour or so on the net; other than where to buy them for too damn much when I don't even know if it's the motor. The closest I come to DC and motors are ECMs; but they have line voltage to the module and are controlled by DC voltage. I can't relate to this guy at all.
Cambridge Motor Works
Model JM01-011
Volts DC 90
RPM 3200
Amps 21
Continuous duty DC permanent magnet
2.5 HP
So we have 110 AC to the board and then what? It's converted (inverted? That's typically DC to AC?) to DC and sent to the motor? Does it deliver more DC voltage as more speed is called for? My hvac meters will only do microamps dc and not nearly on a large enough scale to handle something as large as 21 amps DC. So may I simply, using watts as a constant; just figure DC amps using ohms law once I have the AC watts?
Can't find any detail or schematics re: the components that would typically shed some light...
It's working at the moment. In the past the deck would just have to be waxed. But the other day it acted like it didn't want to go even with help. Just hummed. I popped the hood and immediately went to vacuum the crud out, disconnecting power and using the dedicated plug for the wet/dry vac. In doing so I guess I rebooted it and it came back to us. When it was hesitating you could clearly hear a relay click on the board, so I figured I'd be looking at voltages from the board to motor or the motor itself if it happens again.