# Electrical Guru’s Here here!



## HuD_91gt (Jan 9, 2022)

Hello everyone,

I recently purchased an RF45 clone ZAY7945FG/1 with an electrical issue.

I will start off, I am no guru with AC electrical, but am fairly competent when it comes to DC systems. I figured I should be able to troubleshoot this.

So the machine is wired for 240v, and when the electrical contractors are pressed the motor runs as it should (both forward and reverse).

I’ve tried following the voltage from the outlet into the machine, and it seems to disappear at the CU-11 Contactors (a form of relay I assume?)

There is 23v pretty much everywhere where 120v is not seen (using one side of voltmeter grounded).

I tested continuity at the 3 safety switch I found (protection shield, then two on the quill).  They seem to work fine while measuring 23v.

I have no wiring diagram for this exact machine.

transformer shows proper voltage at input and output is also 23v.

There is no sign of 120v in the electrical “button panel (emergency stop etc).”  23v again.

The 2amp ceramic fuse checks out.

Any input is greatly appreciated.


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## HuD_91gt (Jan 9, 2022)

Here it is next to my import mill.


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## Reddinr (Jan 9, 2022)

The contactors are a type of relay.  They are normally open and close when they are turned on.  Quite often there is a "sealing contact" on the motor contactor.  That closes when the start button is pressed and the contactor pulls in.  That is wired in parallel with the start button which is why the start button does not have to be held forever because the auxiliary contact of the contactor "seals" the circuit.  The stop button is normally closed (has continuity) when NOT pressed and opens when pressed.  When working right, the stop button breaks the circuit, the contactor drops out and the start button will need to be pressed again to start things again.  That is, if all is working.  From your photo, the top contactor with the over-load unit to the left appears to be your motor contactor.

Don't forget, there's high voltage in there that can bite you so be careful.

Please confirm that you have a start button, a stop button and an emergency off (EMO) button type circuit.  Is the emergency off button a momentary one or one you have to twist and pull outward to reset?  If it is one that has to be reset, do that first.  Is there 23 VAC on both sides of the EMO after it is reset?

If that is not it, I would try this:

Look for the 23 VAC on both sides of the start button contacts.  It should be always present on one side and only present after the button is pressed on the other side.  Pressing the start button should start it again...

Read the contactor coil ratings.  Are they the proper coils?  Did they put a 220VAC coil in the contactors by mistake?

Try this and get back to us.


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## Reddinr (Jan 9, 2022)

This is a classic motor start/stop circuit.  It is probably not too unlike what you have there.  The EMO would likely be between the fuse and the stop button contacts.  The "M" is the contactor coil and aux contact.   There may or may not be other normally closed contacts in the circuit that are in series with the stop button or in series with the "M" coil.   These circuits can vary.  For example, this one has two stop and two start buttons.  Ignore the extra buttons in this circuit.  The OL (over-load) senses motor current and will open if the motor is overloaded for too long.  There is a reset button right on top of it.  Come to think of it, try resetting the "OL" using the button on the OL.


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## Reddinr (Jan 9, 2022)

How the above works:

Starting out, if the OL has been reset (closed), the motor is in the off condition and the EMO is reset, there is voltage (24VAC) provided to the stop button's left contact.  Because the stop button is normally closed, voltage is present at the right-hand side of the off button contact.  Once someone presses the "Start" button, current can flow to the (M) contactor coil and then the M contactor is powered and it's auxiliary contact closes.  Once the aux contact -| |- "M"   closes, that "seals" the current flow around the start button  -|\|-  and is the reason that you don't have to hold the start button forever.   To stop the motor, a stop button is pressed, interrupting the current to the (M) coil which puts things back to the original state, ready to start over.

If the motor is overloaded, the "OL" opens up which keeps the motor contactor from being turned on until it is reset.


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## HuD_91gt (Jan 9, 2022)

Wow. What an amazingly quick reply. I am going to go over your post with a fine tooth comb after I finish making lunch. I quickly went down and tested the emergency stop switch. It is of the twist and pull type.

It has 23v coming into both sides (3) of the switch, then alternates between the two on the other side(5 and 17) pending the position of the switch. Unless wired incorrectly I’d say the switch is working correctly.


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## markba633csi (Jan 9, 2022)

Agree with Reddinr, also:  You don't want to be referencing your meter from ground on the 24 volt side of the transformer.  You should have one meter lead on one side of the transformer 24 volt output and use the other meter lead to probe around the 24 volt path.  The 24 volt system may or may not have one side of the 24 volt supply tied to ground by the factory- best to assume it is not- it can give confusing readings
-Mark


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## Reddinr (Jan 9, 2022)

Hard to tell for sure from the photo but it looks like wire 2 ties the transformer to ground.  Easy to check on site.  Still, Mark has good advice, best to be sure.

I have to step out for a few hours.  Will try to check back in this evening.  Good luck.


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## HuD_91gt (Jan 9, 2022)

Ok. I’ll posted a little bit at a time as I work my way through this.

Thank you both for your help.

The start button shows 24v on one side. Once activated, 24v shows on both sides. Then the “off” selector is switched to off. The one side of the start switch goes back.

so it seems to allow the voltage to go through as you describe, and hold it close until the power is interrupted.



How do I reference the 24v system if I should be using ground?

I can’t find a O/L switch in this motor.  I do see some sort of load protector in the control box (with the red and dark blue buttons).   I did reset that.  More of a theory question about the O/L…. If it’s tripped, would the motor still run when I press the contactors?


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## Reddinr (Jan 9, 2022)

The O/L should be the top, left item in your first photo.  It is connected mechanically/electrically to the top contactor.  If it is tripped, the contactor will not close and the motor will not run.

The circuit I sent is too simple.  There is forward / reverse and Jog in your box.  This diagram may be a little closer but not really that close. (Does anyone have the diagram for an RF45 like this one?)   I couldn't find a better one in a short time looking.  The story here is that a JOG button only closes one of the contactors for as long as you hold it in.  It is like a start button without a sealing contact.  Only one of the contactors should turn on at one time.  One is for forward and the other for reverse.  I'm guessing that is what you have there.  

Check to see if there is a wire from one side of the 24 VAC to ground.  If so, you can use ground as the reference.  If not, use the low voltage terminal on the transformer that show a voltage when you measure between your EMO and the terminal.  The other terminal (not the common terminal) would show ~0 Volts AC.


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## JimDawson (Jan 9, 2022)

I would not expect to find any 120VAC in that system.  The main power is 240VAC and the control power is 24VAC.  In reading your first post it would seem that everything is working normally.  If all the functions work as they should, then I think you are OK.  The only thing that I would concern myself with is that the machine is properly grounded.


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## HuD_91gt (Jan 9, 2022)

Hi Jim.

As stated before. My AC knowledge is lacking. The 120 v reference is seen when the multimeter is connected to the ground “bus bar” of the machine.  I am in Canada, so our 240v is built up of 2 120v lines.

when connecting the multimeter between each of the 120v lines from the house, they combine and get the 240v.


Perhaps I’m not quite understanding your comment? The functions of the machine are not working properly. The electrical contactor for the relays needs to be pushed for the motor to be turned on. The buttons on the control panel at this point do nothing.

I’m still having trouble getting an understanding of transformer referencing line.  
There is 2 low voltage connections on the transformer when referencing ground and 2 at 120v.   Is it possible for someone to dumb down the explanation when referencing the emergency cut off as described above?

it does not look like the transformer is connected to ground at all.


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## JimDawson (Jan 9, 2022)

I kind of misspoke there, yes, you would see 120V between ground and one of the hot legs.  But that 120V is not used in any part of the circuit.  That's the way North American power is wired at the pole, each leg is 120V to ground (neutral)

Not sure about the E-stop button.  Does it seem to work as expected?  Maybe I misunderstood your post.


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## HuD_91gt (Jan 9, 2022)

Reddinr said:


> The O/L should be the top, left item in your first photo.  It is connected mechanically/electrically to the top contactor.  If it is tripped, the contactor will not close and the motor will not run.
> 
> 
> 
> ...


In regards to the emergency stop I was talking about the comment quoted here. I don’t quite understand it. (Saying that the over load circuit I found is the one described above). It seems fine.

Contactor seem to be labelled correctly?


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## JimDawson (Jan 9, 2022)

OK, now I think I understand.  If you manually push in a contactor the motor will run?

I can't seem to load the picture, maybe you can repost it.


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## HuD_91gt (Jan 9, 2022)

JimDawson said:


> OK, now I think I understand.  If you manually push in a contactor the motor will run?
> 
> I can't seem to load the picture, maybe you can repost it.


Yes exactly. Manually push the contactor and the motor runs. Manually push the other contactor the motor runs in reverse.


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## JimDawson (Jan 9, 2022)

HuD_91gt said:


> Yes exactly. Manually push the contactor and the motor runs. Manually push the other contactor the motor runs in reverse.



OK, that is what I would expect.

Yes, the contactor seems to be labeled correctly.

If nothing works, the first thing I would check is the E-stop switch contacts.  About 80% of the time this is the problem.


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## HuD_91gt (Jan 9, 2022)

I have gone over the emergency stop button as described previously. It seems to be working correctly.

How do these systems operate? Obviously the motor used 240v.   Is the 24v system used to just decrease electrical noise in the control box? What is the point of dropping the voltage.

I’ve gone over the CNA-2 relays. They seem to have continuity.   One pole loses continuity when certain switches in the quill are activated. This is obviously to deactivate the forward rotation, then start the reverse rotation.

I mean I haven’t written out a complete diagram for this but everything seems to connect. The only part I don’t understand is what turns the relay to turn the high voltage power to the motors? I assume the big CU-11 looking relay things. They have high voltage going in one side, and just can’t seem to get it going out the other. LOL!


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## JimDawson (Jan 9, 2022)

Hard to see from your pictures, but it looks like the CU11's are the motor contactors.  

Did you disconnect the wires from the red contact block on the E stop button and measure the continuity across those terminals, with an ohm meter, with the E stop button pulled out?  The reading should be near 0 ohms.

The 240V is the motor power, the 24V is the control power.  It is done this way so there is not 240V across the switches on the machine.  It's safer.

What is the red button on the green wiring block in your first picture?  Is that the fuse holder?


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## HuD_91gt (Jan 9, 2022)

Resistance across the B side of the E stop Button (I assume this is what you mean by red side? It’s orange in my side, vs green on the other side) I get 0.001-0.000ohms. Wires were disconnected.

The red button is the fuse. It tests ok.

thanks for the help with this everyone.


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## HuD_91gt (Jan 9, 2022)

One thing i have found wrong is the green FWD light is burnt out. Lol.


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## HuD_91gt (Jan 9, 2022)

I found this online, although it doesn’t seem to be of much help.


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## JimDawson (Jan 9, 2022)

OK, orange instead of red.  Near 0 ohms is good.

Does that machine have a movable chip shield?  I have heard of those being interlocked with a switch.


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## HuD_91gt (Jan 9, 2022)

JimDawson said:


> OK, orange instead of red.  Near 0 ohms is good.
> 
> Does that machine have a movable chip shield?  I have heard of those being interlocked with a switch.


It did. The switch is placed in the correct position for continuity.


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## JimDawson (Jan 9, 2022)

If there are any other interlocks, check those.

Then my next step would be a auxiliary contact blocks on the front of the CU-11 contactors.  The control power should be connected through the Normally Closed (NC) contacts.

I can't read any wire numbers in your pictures, so can't help you there.


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## HuD_91gt (Jan 9, 2022)

You can’t see any of my photos? I can try uploading off the forum server if need be.


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## JimDawson (Jan 9, 2022)

I can see the images, but they are not clear enough to read any labels on wires and components.


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## HuD_91gt (Jan 9, 2022)

Ah ok. I can try and get some more detailed photos later/tomorrow.

I was just inspecting an RF45 manual, I don’t think the wiring is the same as my mill but I think something clicked in my head.   Should I be getting 24v across the 2 low voltage terminals of the transformer(terminal 30 + 31)? I am getting a reading of 0 volts.


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## JimDawson (Jan 9, 2022)

Yes, I would expect 24V across 30-31.  Are you getting 240V across 20 - 21?


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## HuD_91gt (Jan 9, 2022)

Ugh. That’s not good.
But to answer your question, yes 20/21 show 240v (actually 210v, all my house seems to give).


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## JimDawson (Jan 9, 2022)

Um, 210 is a bit light.  Not impossible if your neighborhood is wired for 208/120, but this is not common except for institutional (like schools, many hotels, and the like) and some commercial power systems.  Most residential is wired for 240 split phase (120, 0, 120).  If you have 120 to neutral from each hot leg, but only 210 between the hot legs, then I would take a serious look at the wiring to your house.

In any case, it sounds like you have a bad transformer.  Normally about the last thing I look at.  Even at 210v in, I would expect around 21 volts out of the transformer (10:1 turns ratio).


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## HuD_91gt (Jan 9, 2022)

I’m in a townhouse complex so that may be part of it. I have 118vish at each leg, and 208ish when connected together.

Is there anyway to troubleshoot the transformer? Would hate to replace it only to find some how someone messed up the wiring and was feeding it 24v from the other side somehow.
Initially I was getting 24v to each side, with the other side of the multimeter on a ground. Could that have fried it?


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## JimDawson (Jan 9, 2022)

HuD_91gt said:


> I’m in a townhouse complex so that may be part of it. I have 120v at each leg, and 208ish when connected together.
> 
> Is there anyway to troubleshoot the transformer? Would hate to replace it only to find some how someone messed up the wiring and was feeding it 24v from the other side somehow.
> Initially I was getting 24v to each side, with the other side of the multimeter on a ground. Could that have fried it?


Ahh, a townhouse, with all gas appliances I would assume.  That would explain 208V

No, testing the transformer with a multimeter could not possibly damage it.  One thing I have found on autoranging digital multimeters is sometimes they will fool you by reading what you expect, but you fail to notice the *mV* over in the corner of the display rather than *V* so you are actually seeing millivolts rather than volts.  I have been caught by this more than once.  Perfectly possible to have a few millivolts just floating around in the air.

To test the transformer, disconnect the wires and measure across 20-21 and 30-31 with an ohm meter, the reading should be <100 ohms on either side.


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## markba633csi (Jan 9, 2022)

Sometimes the transformer wires will come loose or break right at the terminal block- also I have seen cold solder joints from the factory that work for a while then fail after a bit of vibration, heat, and humidity.  You may have something like that going on. It may be necessary to remove the transformer completely to give it a good inspection and/or repair and bench test. Be careful to shut off power before working on it.
-Mark


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## HuD_91gt (Jan 9, 2022)

Well I took the transformer out. The high voltage side the wires are almost non existent on one terminal, and honestly I didn’t see them on the other. So if it wasn’t broken, it is now. Lol. I shoved my multimeter in the whole to see if I could get continuity and no reading.   The high voltage side showed 20ohms.


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## JimDawson (Jan 10, 2022)

Sounds like you found the problem.  Rather unusual for a transformer to fail.


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## HuD_91gt (Jan 10, 2022)

Well I hope it’s the problem. I tried taking it apart but I can’t find the one wire.

searched Alibaba.com  for a new one. Nothing stands it as exactly the same and that concerns me. Grizzly g0761 seems to have a direct replacement but it’s on back order.

then came across this one. I’m thinking it should work, it’s old, but Japanese made. I bet it would last 5x what a good Chinese one would.









						100 VA Transformer Type TRH-2
					

Specifications Model TRH-2 Made In Japan Condition Used Assembled Dimensions: 4 x 3.5 x 4 inches General Transformer Type Dry Auto VS Isolation Auto Electrical kVA 0.1 kVA Primary Voltage 220 volts Phase Single-phase




					www.lenmark.com
				




thanks again for all your helps guys. I can follow wires, but as I said, AC is a bit of a grey area for me.


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## JimDawson (Jan 10, 2022)

That transformer looks like a perfect replacement.


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## Reddinr (Jan 10, 2022)

Suggest one more quick measure of the transformer AC voltage across 30-31.  Keep an eye that the meter is on the "AC" range and an eye for V vs. mV on the readout as suggested above.  I've more than once tried to measure AC while on the DC range by accident and it reads about 0V.  For your question above, measuring the voltage in various ways will in no way harm the transformer.

The low input voltage of about 210 VAC instead of 230 VAC would lead to about 22-23 VAC on the output of the transformer like you reported prior when you were measuring from ground.   If the transformer is NOT grounded that can just be a ghost reading.  However, did you confirm if the transformer is tied to ground?  To do that, unplug the mill from the wall and measure for continuity between 30 and ground and 31 and ground.  Do all of the green terminals you metered to also tie to ground?

It very well could be a bad transformer but worth a quick re-check I think.


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## markba633csi (Jan 10, 2022)

For this kind of stuff, you can treat it like DC; you still need to have a complete circuit with no opens, and a good power source
-Mark


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## HuD_91gt (Jan 10, 2022)

Reddinr said:


> Suggest one more quick measure of the transformer AC voltage across 30-31.  Keep an eye that the meter is on the "AC" range and an eye for V vs. mV on the readout as suggested above.  I've more than once tried to measure AC while on the DC range by accident and it reads about 0V.  For your question above, measuring the voltage in various ways will in no way harm the transformer.
> 
> The low input voltage of about 210 VAC instead of 230 VAC would lead to about 22-23 VAC on the output of the transformer like you reported prior when you were measuring from ground.   If the transformer is NOT grounded that can just be a ghost reading.  However, did you confirm if the transformer is tied to ground?  To do that, unplug the mill from the wall and measure for continuity between 30 and ground and 31 and ground.  Do all of the green terminals you metered to also tie to ground?
> 
> It very well could be a bad transformer but worth a quick re-check I think.


Thanks for the very detailed response. I really appreciate it.  Last night I took apart the transformer, trying to find the hair width copper strand which connected 20/21. It’s MIA and if it was there, I can’t find it anymore to resolder.

The gentleman I purchased the mill from actually works for the company where that transformer posted above is located. So he is getting me his price and should have it fairly soon.

I wasn’t able to test for ground as your described, I just looked for some sort of ground wire and assumed that was a no. I suppose a mute point now.


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## Reddinr (Jan 10, 2022)

Great!  You should be up and running in no time.

One of these should work too.  Not sure about shipping to the great white north...   This is from AutomationDirect.com.
There is also a 75VA choice for $62.  Be sure to look at the dimensions to be sure you have the space for whatever transformer you choose as size can vary a little bit even with the same VA rating.


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## mksj (Jan 10, 2022)

The output wire should be heavier gauge, as it needs to handle up to ~3A, most likely you are not seeing the wire as it may be connected behind the plastic screw terminals. Per what Reddinr mentioned, make sure the dimensions of the transformer fit into the current space available. I do find it very unusual for this type of transformer fail, it usually is fused for overload. It may also be that the higher voltage rating may be unloaded, loading a transformer can usually pull down the output voltage around 7-10% depending on the transformer.


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## HuD_91gt (Jan 10, 2022)

mksj said:


> The output wire should be heavier gauge, as it needs to handle up to ~3A, most likely you are not seeing the wire as it may be connected behind the plastic screw terminals. Per what Reddinr mentioned, make sure the dimensions of the transformer fit into the current space available. I do find it very unusual for this type of transformer fail, it usually is fused for overload. It may also be that the higher voltage rating may be unloaded, loading a transformer can usually pull down the output voltage around 7-10% depending on the transformer.


Those terminals can be removed.  The connecting wire is in those sheathes.   The terminal with the missing wire, it’s sheathe was actually a different darker colour, possibly burnt.

I’m hoping the transformer fits, it is slightly bigger, but should be close.


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## HuD_91gt (Jan 10, 2022)

While waiting for this wiring issue to figure itself out, I spent the day cleaning up the machine. Both cosmetically and a thorough cleaning of the ways.  Super happy with how X and Y move, but Z still seems super tough to go up. Not sure what is normal, but it is an Armstrong excercise. I feel much better about paying way too much for a broken machine now though. Lol

mince I get the wiring figured out, I’m going to do a single point oiling modification.


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## markba633csi (Jan 10, 2022)

Mark J. is right, the wire on the transformer output side would be fairly hefty like 18 gauge so it's probably hidden under plastic.
Also, you can always mount the transformer outside the box and run wires in if you have to, if you just can't stuff it in there
-Mark S.


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## HuD_91gt (Jan 10, 2022)

This is when I got it…


markba633csi said:


> Mark J. is right, the wire on the transformer output side would be fairly hefty like 18 gauge so it's probably hidden under plastic.
> Also, you can always mount the transformer outside the box and run wires in if you have to, if you just can't stuff it in there
> -Mark S.







This is with the terminals removed. They are connected by wire.


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## markba633csi (Jan 10, 2022)

That's sure a mystery to me. I can't make hide nor hair out of it, but from where I'm sitting it's really hard to tell. The open could be on either side.
Most likely on the 220 volt side since the wire is so thin
The 220 volt side should certainly be thin wire like 34 gauge, but the 24 volt side should be considerably thicker like 18-20 ga


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## HuD_91gt (Jan 10, 2022)

markba633csi said:


> That's sure a mystery to me. I can't make hide nor hair out of it, but from where I'm sitting it's really hard to tell. The open could be on either side.
> Most likely on the 220 volt side since the wire is so thin
> The 220 volt side should certainly be thin wire like 34 gauge, but the 24 volt side should be considerably thicker like 18-20 ga


Yes it is on the high voltage side…..
So I’m not sure how I was getting 24v on the other side.  We will soon see…


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## Reddinr (Jan 10, 2022)

A couple of thoughts. 

First, be sure the fuse to the transformer is sized close to the transformer rating.  50 VA would be about 1/4 Amp at 210V.  So, no more than maybe 1/2 Amp at most.  Do this especially on the first turn-on (Try starting with a 1/4 Amp slow blow) because maybe there is a short circuit that opened the primary coil vaporizing the wire you can't find.  The fine wire can get weak due to vibration and can go pfffft before the fuse.  Who knows at this point though.

Second, some people have put a cable-connected counter-weight on the Z axis to take some of the weight off.
Here's a fancy brake-rotor-based one that came up when I googled "z axis mill counter weight".


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## HuD_91gt (Jan 10, 2022)

Reddinr said:


> A couple of thoughts.
> 
> First, be sure the fuse to the transformer is sized close to the transformer rating.  50 VA would be about 1/4 Amp at 210V.  So, no more than maybe 1/2 Amp at most.  Do this especially on the first turn-on (Try starting with a 1/4 Amp slow blow) because maybe there is a short circuit that opened the primary coil vaporizing the wire you can't find.  The fine wire can get weak due to vibration and can go pfffft before the fuse.  Who knows at this point though.
> 
> ...


The fuse for the transformer…   I only know of the one fuse under that whole panel. It’s listed as a 2amp. I should probably ensure it’s correct.


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## Reddinr (Jan 11, 2022)

That 2A fuse is likely the one for the transformer, however, it may be on the output of the transformer.  Maybe trace some wires to see how it is connected.  2A is probably about right for an output fuse given the size of the contactors you have there.  If it is an input fuse it would be a bit large I would think.


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## HuD_91gt (Jan 11, 2022)

It’s an output fuse for sure. I don’t see any fuse on the inside. After reading, it says if any I should have an input?

weird.


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## Reddinr (Jan 11, 2022)

You are probably just fine with only an output fuse.  It protects the transformer from overloads and shorts of the low voltage circuitry.  The transformer primary kind of protects itself if the transformer shorts out internally.  The tiny wire just vaporizes and you're done.  Having a primary fuse on the transformer may be very slightly safer for a small transformer like this but I wouldn't worry about it as long as you keep the covers on your control box.  If the transformer shorts then it has already gone to meet its maker anyway.  A primary fuse might blow but then you need to buy a transformer AND a new primary fuse...   It is a different story for larger transformers where you want a primary fuse or breaker to protect input wiring and the transformer.


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## tq60 (Jan 11, 2022)

You stated you had 24 volts on output of start switch when pushed, this indicates transformer good.

Pushing contractors to make motor go proves high voltage good.

Look closely at contractors.

There will be high voltage on all but 2 or 3 wires.

The coil wires are what you need to identify.

Start at your stop switch.

Get a roll of masking tape and a sharpie.

Make tags and number them in pairs, 1a, 1b 2a, 2b and so on.

Sheet of paper to describe your system.

Start and do this.

Place tag 1 at wire on Start switch that is switched output, the one that changes.

On paper note wire 1a switched 24 volts from Start switch.

Carefully follow the wire to where it goes and tag it with the b side and note where it goes.

Check voltage both ends to be sure, should act same at both ends.

If not you lost the wire or wire open.

With both contractors not working you likely have. Ommon problem and not open coil.

When the wire goes to a switch, check it with voltmeter.

If a contactor coil check voltage too but also check other side of coil.

If you get 24 vac on both sides then the ground is not connected.

It could have an interlock that removes ground to prevent operation.

Continue to tag and trace the wires as that is the path the current flows and it must get back to the transformer.

Sent from my SM-G781V using Tapatalk


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## HuD_91gt (Jan 13, 2022)

^^^ I’ll go through this. I’m starting to understand how this works now. Basically a series of relays which eventually lead to the main high voltage contactor.
Easy enough to figure out if I just draw it all out…. But, Before we get to that point.
My old transformer is toast, whether from me, or it was toast already… but I do have the new one now.

It squeezed in with a single tapped screw and fits like a glove (although bigger).

Im having an issue understanding how the output should be wired though.  I have a feeling I could wire it either way but just want to be sure.

I tested the transformer resistance Input side was 0.012kOhms, and 0.015 for the 200/220v inputs. I wired for the 220v using the 220v input.

when powered up, I get 23.3 v out the output. I assume this won’t be an issue. If it is, I can probably go down to 200v input and the 22v output to get the voltage im looking for. It’s a guess but maybe. lol.

Now if someone could help me with the other wires. Lol.

The input was easy, as the old transformer used a single input for 240v or 380v, you just move the other wire to your desired input.     The output side is more challenging as it uses a completely different set of inputs for each “choice”.

I should also mention I removed the “chip guard” switch completely.  I knew it was going to fumble me up if I still had it on there, somehow getting moved to the wrong position. It was easy enough to figure out how to jump the wires.  My brain says leave it along until you figure out the other issues, but I had idle time! Lol and I didn’t see the reply above either. Haha but couldn’t start on that until I had a transformer.


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## tq60 (Jan 13, 2022)

Transformer should have 4 wires.

2 input and 2 output.

Does not matter which way on either, input goes to line cord via main switch or fuse.

Output goes to everything else.

It is alternating currently polarity does not matter.

After connected plug in, turn on and see what happens.

Confirm your 24 volts at start then continue.

Exact not critical, 22 to 26 will work.

Sent from my SM-G781V using Tapatalk


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## HuD_91gt (Jan 13, 2022)

It Works! That sweet sound of import precision straight cut gears! Thanks so much guys!

I’m honestly still a bit dumbfounded how I could have possibly been getting 24v out the other side, with a botched transformer. But hey. Saw something off and went with it!


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