welded contactor

[timebuilder]

I would recommend that "sitting on the bucket" process.

If the windings are good and there are no shorts to ground, the idea that this is being caused by the compressor is possible, but not great.

Most likely, the reference to chattering (an intermittent condition in the control circuit that causes the contactor to pull in a drop out rapidly) is the real cause.

Most of the time, I find a defective pressure switch/ loose wire nut/terminal connection/worn thermostat micro relay that causes chattering.

I have never replaced a compressor yet for this condition that checked out properly with the meter.

[Tommy knocker]

I would start with control Circut as well. The TDOB and isolation relay ideas are both very good ideas. I would be looking for voltage drop on control circut. The TDOB should tell you for sure though. If it welds with it in then it's on the line side, comp. if it stops welding it get your stool out and start tracing that control Circut out. Ther time delay may treat the symptom but will not fix the problem. Good luck.

[mikeacman]

I would start with control Circut as well. The TDOB and isolation relay ideas are both very good ideas. I would be looking for voltage drop on control circut. The TDOB should tell you for sure though. If it welds with it in then it's on the line side, comp. if it stops welding it get your stool out and start tracing that control Circut out. Ther time delay may treat the symptom but will not fix the problem. Good luck.

I'm teliin troy you have a stool on your truck

[timebuilder]

I would start with control Circut as well. The TDOB and isolation relay ideas are both very good ideas. I would be looking for voltage drop on control circut. The TDOB should tell you for sure though. If it welds with it in then it's on the line side, comp. if it stops welding it get your stool out and start tracing that control Circut out. Ther time delay may treat the symptom but will not fix the problem. Good luck.

Some delay on break modules will not react quickly enough to accomplish this purpose, when the chatter rate is high enough to retain sufficient voltage through the module to keep it turned on, yet not enough to hold the armature of the contactor in the energized position.

[mikeacman]

Some delay on break modules will not react quickly enough to accomplish this purpose, when the chatter rate is high enough to retain sufficient voltage through the module to keep it turned on, yet not enough to hold the armature of the contactor in the energized position.

agreed...

I would use a three wire....supposed to be less problematic in respect to the above issue