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SL82
05-06-2009, 03:26 AM
Came across a CSR compressor that had past issues with the potential relay. As I followed the wiring through to make sure it was correct I found that the wires that were supposed to go to terminal 1 were on terminal 2 and the wires that were supposed to go to terminal 2 were on terminal 1. These terminals are the contacts for the relay but #2 is the other side of the relay coil (#5 - #2) It was running like this for a while. I know its wired wrong but I dont really understand what its doing or the effects of being wired this way any thoughts?

Z4Y
05-06-2009, 03:40 AM
could you attach the drawing or diagram for that.maybe i can help

SL82
05-06-2009, 04:08 AM
I dont have a diagram. All csr motors with potential relays are wired the same. I will see if I can find one online. You can probably find a diagram in a text book somewhere.

Magoo
05-06-2009, 06:16 AM
Are we talking capacitor start relay as in CSR.
Have you checked the actual windings / as in start and run with an ohm meter.
Have you check function of start relay as such, again with an ohm meter.
Me thinks that if crossed over one of two things will happen real quick.., 1/ the comp will trip on Klixon overload . 2/ the start capacitor will explode.
magoo

nike123
05-06-2009, 08:11 PM
http://pdf.directindustry.com/pdf/embraco/compressor-handbook/17666-31450-_28.html

Gary
05-06-2009, 09:11 PM
The purpose of the capacitors is to shift the phase in the start winding and thus boost the rotational torque.

The start capacitor provides more torque than the run capacitor.

When the motor gets up to speed, the contacts open and the start capacitor in circuit 1-4 is disconnected while the run capacitor in circuit 2-4 remains connected.

If 1 and 2 are swapped, then the (higher torque) start capacitor will remain connected while the (lower torque) run capacitor is disconnected. This will overtorque the windings and eventually destroy the compressor.

Yuri B.
05-06-2009, 09:28 PM
(Many) start capacitors may stay powered for seconds only, if by a fault they are connected for longer, they overheat and may blow up.