Enco transformer help

I would assume the transformer is getting power and just measure the output for now, for safety's sake
-M
 
I would check the pull in coil on that contactor.
Should have 24volts supplied. If you don’t 24 volts check the fuses. If the coil is bad, infinity reading between terminals with #6 wire based upon the diagram disconnected so that you are only testing the coil and not the whole system, then replace the coil or the whole unit.
 
Z2V said:
I’ll ask the obvious because I see a fuse in the bottom of the cabinet. Are both fuses good? Do you have a meter? In the picture if you put your meter leads across the two red wires on top of the transformer you should read 220 volts AC. On the bottom of the transformer reading across the first two wires on the left side you you should read 6 volts AC. Moving over to the next three wires on the bottom it looks like the first wire is white. Put one meter lead on it and read to each of the next two wires and you should get around 29 volts they way it looks
Click to expand...
i made a mistake in the first post. that picture of the electrical box is one I got off the net that looked close to mine. When i went out this morning to follow your instructions i see now my transformer is different. going from left to right i have nothing on the first 3. I tried testing them across each other and to ground individually. I do have 29 on last 2. The Schematic is also one I got off the net, It says its for my machine but now im not so sure. Just FYI. I know very little about wiring so detailed info is a big help. thanks

IMG_0379.JPG
 
This pic is your actual transformer and you have 29 volts on the last two bottom terminals your transformer is OK. The first wire from left is yellow/green and looks to be labeled PE is ground. Do you get a reading between the third and fourth wire? I would look for maybe 6 volts that would be the power for the lights. The 29 volts on the last two terminals is for the relay coils.
Like Mark mentioned, it’s likely a safety switch gone bad. It could possibly be a relay coil bad but that is about as unlikely as a bad transformer.
Disconnect the power and go to each of the switches and remove one wire from the switch and then check for continuity across the switch terminals. You want the switch out of the circuit to test it that’s why I mention removing one wire.
‘Did you check the fuses? Check them for continuity with your meter.
 
Z2V said:
This pic is your actual transformer and you have 29 volts on the last two bottom terminals your transformer is OK. The first wire from left is yellow/green and looks to be labeled PE is ground. Do you get a reading between the third and fourth wire? I would look for maybe 6 volts that would be the power for the lights. The 29 volts on the last two terminals is for the relay coils.
Like Mark mentioned, it’s likely a safety switch gone bad. It could possibly be a relay coil bad but that is about as unlikely as a bad transformer.
Disconnect the power and go to each of the switches and remove one wire from the switch and then check for continuity across the switch terminals. You want the switch out of the circuit to test it that’s why I mention removing one wire.
‘Did you check the fuses? Check them for continuity with your meter.
Click to expand...
I did check the fuses with a meter and they are both good, I do get a reading of 29 between the 3rd and 4th WIRE, I do not get a reading between 3rd and 4th terminal. ( #2 is not used). I tested both the E stop and the green start/power buttons with a wire off and they both seem ok. I get continuity when pushed on green or pulled on E stop. Would it be ok to take one wire off the switch and connect it to the other wire to make the switches constant on for right now? that way when i power it on I should get juice to #6. and that should make it easier to test for power. Is that correct ?
 
You mention #6, looking at the diagram you posted that’s the coil for KM1 relay? If that’s the case leave everything wired as is and measure for voltage from #6 and the white wire on the bottom of the transformer while you have it turned on to run. If you have no voltage move to #5, 4, 3 while leaving the other lead on the white wire on the transformer.
Also, I see an “FR” contact in line with KM1 and also in line with the motor leads. This could be an overload that might have a reset button
 
KM1 is the power latching relay, KM2 and KM3 are the motor run relays. KM1 should latch on power up with the spindle switch in the stop position or there is a start button, if not most likely it is a faulty contactor coil. Almost never see a transformer fail, in particular where the taps are fused. The indicator lights are 6V, if KM1 is closing it should latch. So I would check the function of that first. If there is a belt cover switch or guard switch which it looks like after the E-Stop switch then most likely that is faulty.

The pictures and schematic are too poor resolution to really see the details. When measuring the transformer voltages, you measure from the 0V tap to the voltage tap (6V, 29V). The red wires are the transformer voltages, basically you start out measuring voltage from the 0V to the 29V starting at the transformer terminal and at each step forward, wires numbered 1, 2, 3, 4 and 6. You would also measure voltages a A1 and A2 on the K1 power contactor to see if it is getting power to the coil. If there is power to the coil and it is not closing then the coil has failed (you can also disconnect A1 and A2 and measure the coil with an ohm meter and see if it is open). Be mindful that the black wires are hot with 230VAC so a short when probing voltages could be very serious. I would suggest if you do not know how to check the voltages that you find someone who is more familiar with electrical equipment. If one needs a contactor replacement, one would need the specific model number and possible checking the top contact block as to NO/NC configuration. There are Baomain AC contactors that seem to be the same style, but you world need to match up the same specifications and configuration. Most likely I would think their is an interlock switch that is either become misaligned or failed, you can put a jumper across the switch or check it with an ohm meter with the wires disconnected.
Just an example. https://www.amazon.com/Baomain-Contactor-CJX1-22-3-Phase-3-Pole/dp/B01J9MW0H0
 
Often, the mechanical reversing switch is what fails on these systems. I believe it can prevent the main contactor from latching if faulty. It's the switch or switches mounted near the left hand side of the control shaft, operated by a lever on the carriage. They get a lot of use and are reported to be a common failure point, on lathes with a lot of mileage
They are either a pair of microswitches or a single rotary type switch
If you remove the switches for testing, be sure to label the wires clearly
-M
 
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mksj said:
KM1 is the power latching relay, KM2 and KM3 are the motor run relays. KM1 should latch on power up with the spindle switch in the stop position or there is a start button, if not most likely it is a faulty contactor coil. Almost never see a transformer fail, in particular where the taps are fused. The indicator lights are 6V, if KM1 is closing it should latch. So I would check the function of that first. If there is a belt cover switch or guard switch which it looks like after the E-Stop switch then most likely that is faulty.

The pictures and schematic are too poor resolution to really see the details. When measuring the transformer voltages, you measure from the 0V tap to the voltage tap (6V, 29V). The red wires are the transformer voltages, basically you start out measuring voltage from the 0V to the 29V starting at the transformer terminal and at each step forward, wires numbered 1, 2, 3, 4 and 6. You would also measure voltages a A1 and A2 on the K1 power contactor to see if it is getting power to the coil. If there is power to the coil and it is not closing then the coil has failed (you can also disconnect A1 and A2 and measure the coil with an ohm meter and see if it is open). Be mindful that the black wires are hot with 230VAC so a short when probing voltages could be very serious. I would suggest if you do not know how to check the voltages that you find someone who is more familiar with electrical equipment. If one needs a contactor replacement, one would need the specific model number and possible checking the top contact block as to NO/NC configuration. There are Baomain AC contactors that seem to be the same style, but you world need to match up the same specifications and configuration. Most likely I would think their is an interlock switch that is either become misaligned or failed, you can put a jumper across the switch or check it with an ohm meter with the wires disconnected.
Just an example. https://www.amazon.com/Baomain-Contactor-CJX1-22-3-Phase-3-Pole/dp/B01J9MW0H0
Click to expand...
after doing a bunch of testing and help from a friend who can read the schematic I figured out that I do have power going to coil in the KM1 relay but it is not pulling in. So just ordered 3 . Will update when i get them installed. Thanks so much for all the input.
 
Hi guys, going to jump in on this thread as I have a similar problem with a similar lathe. I have the Harbor Freight 12x36 version of this lathe, almost identical. It also quit on me during the Christmas holidays.
Lathe powered on fine for first use in the morning but when I got my metal chucked up and went to use it there were no power lights on the front. I checked and do have 220v all the way to the machine. I found the light in the power switch had died so i put in a new one. Now when you put power to the machine the power light comes on for a second then you hear a click and the lights go off. The click is the KM1 Contactor closing (the button is pulled in). The lathe will work in forward and reverse as normal at this point but no power lights. If you disconnect power it will not pull in the KM1 contactor though. It blows a fuse (from the left side of the box it is the 2nd fuse)
The Transformer voltage is all over the place, supposed to be 29v but am reading 45-38v, could this be the culprit?
Wiring Schematic.JPG
 

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