Tripping compressor

[WorkshopChris]

I found a good article how to check capacitors on Wiki/Troubleshhoting_logic_board_components

Give that a go as your next thing to look at, some multimeters will have a capacitor test function. But you can try with a basic mm on a resistance setting, you will be looking at an initial change in resistance as the capacitor tries to charge. The next thing is to take measurements of the motor winding coils.

 

[luccass_j]

Findings so far the capacitators are working. They do change the resistance. I also check for continuity between the capacitors and the start button and between the same start button and plug. No fault found so far. Chris to take measurments at motor winding coils i will have to take the motor out am i wright? And i presume they look the same as in cars starter motor.

 

[WorkshopChris]

You just need to open up the terminal box.
As you have said capacitors i presume this is a capacitor start, capacitor run motor.

 

[luccass_j]

Capacitators energise field coils yes?

 

[luccass_j]

Its capacitator start capacitator start motor.

 

[luccass_j]

I mean it is capacitor start capacitor run motor.

 

[123hotchef]

same thing happened on my compressor I swapped the B curve 16amp mcb to a C curve and it has been great ever since

 

[luccass_j]

What is the difference?

 

[luccass_j]

By the where is this terminal box?

 

[dobbslc]

The fact it suddenly stopped working would point to an actual fault rather than a problem with the supply to me. Its worth trying a new pair of caps just in case it's one that's gone dead short but I think it's probably the motor..
You can buy new motors from Machine Mart and its not too painful if you can get a vat free voucher.
My SIP 150 had the same fault and I tried everything but in the end it was the motor, I even measured the windings and couldnt find anything wrong so it was a bit worrying spending lots of cash without knowing if it would fix the fault.

 

[luccass_j]

I agree i do not want to just swapping the parts just to find out they are in working condition.

 

[WorkshopChris]

The capacitor is to create a phase shift to sta

By the where is this terminal box?

This might be part of the box that holds the capacitors some use a separate box with external caps some are all in a big plastic box on the side. What you are looking for are the wires that disappear inside the motor.

There are lots of different posible combinations, you probably have a pair of wires for run windings, a pair of wires for the start windings, maybe running through a centrifugal switch, and possibly a pair of wires for auxiliary winding.
You need to make sure you have a good diagram or photo befor you start.

Your start winding should have a higher resistance than the run winding. although not much difference you will probably be looking for readings in the single figures may be 4 ohms start and 2 ohms run.

Before you start just double check that you have no continuity between any terminals and the metal body of the motor.

 

[luccass_j]

Great i think it is the box that hold capacitors because i do not have any other boxs on the motor. I dont have the diagram and i dont know whats happened with my manual although im usually good with keeping them in one place. I downloaded something for sip compressors but its just basic. Ill try to follow the cables and see where they are leading.

 

[luccass_j]

By the way i did try to look at some compressor motors diagrams on the net.

 

[luccass_j]

Last night i went to the garage to look for the terminal box but there is nothing there the wures just pass through the case under the box with capacitors and thats it. I tried to open the motor. There is a plastic fan at one end and thats the place i could see where the wires are going if i could open it. I tried to pry the fan off but i didnt want to break it so i opened the motir fro the other side. I hade to remoce the pully first. I used a pulley puller and i heated it up once i relised the pully is bending. So i opened the other side but still couldnt get to the wirings/terminals.

Maybe I should buy a new motor.

 

[WorkshopChris]

Maybe I should buy a new motor.

That might be your best bet at the moment if you have disconnected the motor and with the power of making sure you have no continuity between L or N and earth.
Then make sure you have no continuity between L and N with the switch in both positions, then the only thing left is the motor anyway.

Have you managed to remove the pully from the motor?
Don't want to teach you to suck eggs, but have you removed all the grub screws often there is more than one.

 

[daleyd]

That might be your best bet at the moment if you have disconnected the motor and with the power of making sure you have no continuity between L or N and earth.
Then make sure you have no continuity between L and N with the switch in both positions, then the only thing left is the motor anyway.

Have you managed to remove the pully from the motor?
Don't want to teach you to suck eggs, but have you removed all the grub screws often there is more than one.

I've also seen some where one grubscrew is under another to lock it in place, worth a quick check.

 

[WorkshopChris]

I've also seen some where one grubscrew is under another to lock it in place, worth a quick check.

Yes, i often use the allan key as a rough depth gauge to make sure I am down to the shaft or key.

 

[luccass_j]

I did remove the pulley it was interference fit so i used my puller and apply some heat. There were no grubscrews as i said before i managed to open one side of the motor but thats as far as i could go.

I check for continuity between all the cables and the motor case and there is none apart from the earth wire as i woukd expect anyway. But i will check continuity between L and N and earth to rule it out tonight.

 

[luccass_j]

I disconnect the wiring from the motor and capacitor side and i check the continuity between L and N of the wires going into the motor and there is continuity, correct me if i am wrong, but i always thought they should be continuity as it is one circuit. There is no continuity between either L or N and the earth.