Troubleshooting

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nickelec

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Im not so great with motor controls.

So the way this is supposed to work is as follows, when u press the start switch your supposed to be able to move a joy stick which operates the 5 other contacts , but for some reason start switch does not work u have to manually hold in the first contactors and press each individual contactor after that to operate the drill press any ideas?

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Sorry forgot to upload the photos
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I'm thinking that there's something wrong with the transformer I'm only getting 101v but right now I have one and 4 jumped out and all the contactors close and I'm able to control via the joystick

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Sounds like thee control circuit has no power. I'd start with making sure the control power transformer is putting out the 110 volts and that both fuses are good.

Added: Oops, didn't read through your second post. I don't see #1, but if bypassing part of the circuit gives you control, you have control power, so the issue is in the part of the circuit you're bypassing.
 
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LarryFine said:
Sounds like thee control circuit has no power. I'd start with making sure the control power transformer is putting out the 110 volts and that both fuses are good.
Click to expand...
I checked that and I'm only get 101v from transformer leads and from hot to ground 36v .. strange

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So what I did was took an extension cord and hooked it yo the wires that were on the out out of the transformer and got nothing. Then I noticed wile putting back the start stop switch there was a wire not hooked up to it , what wire would you say would cause those symptoms? Came from either the start or stop switch

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I think 1 is the far left attached to the 0v side of transformer

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With no transformer wire grounded, the circuit is floating, so voltage-to-ground readings are meaningless.
 
Looks like it should go to 4 which is one side of the NO contacts on relay C. If it isn't connected (as drawn) nothing below connects to the 0 side of the transformer and only relay C and the power light will work.

Apparently the switch on the top left is a 2PST normally open and is the "on/off" switch supplying power to the indicator light and the coil of relay C. (There are a couple of limit switches in there too.) "EMO" is the mushroom head STOP button.

The contacts C off relay C are NO and when relay C is energized by the ON switch the contacts close and supply power to the rest of the circuit via that mystery wire.

but for some reason start switch does not work...
Click to expand...

Sounds like the coil of relay C is not getting power or it is open and needs to be replaced. Check the EMO switch and the limit switch marked LS as well as the one after that. Does the "power on" indicator light? Measure the voltage on the coil of relay C with the start (on) switch closed. Check the start switch itself.

-Hal
 
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Thinking about this overnight, betcha the lamp isn't a "power on" indicator but a work illumination light. So it isn't a 2PST switch but two simple SPST on-off switches, one for the machine and one for the light.

An easier way to troubleshoot those switches is with a clip lead- a maybe 12" length of wire with alligator clips on each end. If you can get at the limit switch jump it with the clip lead but msny times it's a lot of trouble getting to them. So jump the connections at the wiring in the control panel.

-Hal
 
Schematic doesn’t make things clear. I’d focus on the pump as it eliminates a lot.

If you manually push in C, and pump won’t work I’d be looking at that missing connection from C contact on zero side of control transformer......vertical wire on left side of ladder diagram. Connection isn’t shown, maybe a safety shutdown, foot switch, etc?
 
Here's what you do. Turn the on/off switch to on.

1) Does the light work?
No- Check the on/off switch.
Yes- Does contactor C pull in?
No- Measure voltage on its coil. If 120v replace contactor or coil.
No voltage? Jump the EMO switch then the first limit switch then the second switch (shown just above the C contacts on the drawing) with your cliplead. One of them will make contactor C pull in. Then you know what switch it is that is causing the problem. Either find out why it's not operating properly or if it's defective replace it.

Of course you could also take your voltmeter, connect one lead to the 110V bus on the right (right at the transformer would be convenient) then with the other lead start from both terminals on the EMO switch, then both terminals on the limit switch then both terminals on the second switch. When the voltage disappears you have the winner.

-Hal
 
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nickelec said:
... I have one and 4 jumped out and all the contactors close and I'm able to control via the joystick.
Click to expand...

If you have 4 jumped to the 0 bus yes, the contactors for the joystick will operate but contactor C won't. Contactor C also has 3 contacts in the line coming in for each phase controlling power to the motors and oil pump. So they would not be operating.

This all points to an open from the 0 side of the transformer to the coil of C. If you have a loose wire follow the wiring diagram to see where it goes. I would say that probably is your problem. If not follow the troubleshooting I gave you above.

-Hal
 
hbiss said:
Sounds like the coil of relay C is not getting power or it is open and needs to be replaced.
Click to expand...

My thoughts as well.

Coil "C" appears to be a master relay of some sort that must be energized to allow power to other components. I don't know why the legend calls it "start switch" because it is a relay or contactor more so then a "switch". Any of the contacts in series with it being open or the coil itself being open will prevent the entire machine from operating (other then the work light)

wire #4 is coming off an aux contact on "C". It likely is physically present but not used for anything and is just shown on the drawing. Might be there for options that you don't have installed?
 
kwired said:
My thoughts as well.

Coil "C" appears to be a master relay of some sort that must be energized to allow power to other components. I don't know why the legend calls it "start switch" because it is a relay or contactor more so then a "switch". Any of the contacts in series with it being open or the coil itself being open will prevent the entire machine from operating (other then the work light)

wire #4 is coming off an aux contact on "C". It likely is physically present but not used for anything and is just shown on the drawing. Might be there for options that you don't have installed?
Click to expand...

Crummy drawing, is this a foreign made machine? Wire #4 has to be connected to the aux contact on C for everything below it to be powered. The segment between the two either never got drawn or didn't print.

-Hal
 
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