Tormach PCNC1100 S3 - F6 fuse blown, doesn't move after replacing with new one

Hello everyone,

something weird happen yesterday evening, I was slowly moving Z axis down to place my endmill just above the raw material, the plan was to make a quick conversational program to face the entire block, for this operation I don't use the digital probe. While I did this it studently moved DOWN about 3mm, it STOPPED WHEN THE facemill touched the stock material

Attachment 473046

When I tried to move it up it didn't move, I removed the stock material from the vise to release the tension between the Z axis and mill table , and tried to move it on X and Y .. nothing moved.

I opened the electronics cabinet door and noticed the F6 fuse was blown, I replaced it with a new one today, but when I press the RESET button on the screen, after turning on the mill, it still doesn't move. All the drivers are not powered (no led turned on on drives), also the VFD is not powered.

Attachment 473050

I will check more things now, but first I wanted to write this message , maybe someone had this problem too and it can write down few other things to check.

Thank you

Attachment 473048

I checked the transformer, INPUT / OUTPUT, everything seems fine.

Attachment 473056

Attachment 473058

I will try to focus on this board, the DC BUS board, will check all other fuses and post back if I find anything. The LED is off, anyone around with a PCNC1100 to tell me if the led is always on , when the machine is powered ?

I just checked now, all the fuses on the DC board are OK. Next it's the rectifier diode, but I think I have to remove the board to check that

Attachment 473060

Now I'm worried about the VFD, I don't know why it's not turned on as it's powered directly with 220v AC, I don't know if it has something to do with the DC BUS board, if there is a control line that should be on, and only after that it powers on, the LCD of the VFD is off with the mill turned on, I expected it to be on.

I posted the Electrical schematic that came with the mill, the Relays that power the 48v transformer and the VFD are C1 and C2, but I don't see the control line of those relays in the schematic. I noticed that the Relay that should power on the VFD doesn't activates, the one that powers the transformer activates. The control line of the VFD relay I think it is wire #106 which is energized only when the machine is fully powered on (main rotary switch ON, green button pressed), the other 2 wires L23 and L13 are AC neutral and live, L13 is energized after turning on the main rotary switch, but nothing comes out on the bottom connectors of the relay. I could visually see that the relay is not energized so I removed the relay cover with the label GSC1-1210 and tried to manually press the contactor, after manually pressing it energized and turned ON the VFD, but still the DC BUS board where all the glass fuses are, is not powered, led is OFF.

Attachment 473062

Attachment 473064

My 1100M did the same thing about a month ago. The first thing Tormach had me check was the capacitor output voltage (Cap 300 and 301 on your board). Mine was good and after replacing the fuse the machine was up and running.

It seems the new 15A fuse I mounted has burned ! visually there isn't anything wrong with it, but when I tried to remove the metal covers from the glass it clearly shows it was burned.

I noticed that there is something wrong with the new fuse when I tried again to measure the voltage on the fuse (I tried this to be sure the rectifier bridge diode is ok)

Attachment 473068

After changing it I also removed all drivers connectors, and it seems the Y motor connector, has a darken/burned pin, the PIN was one of the 3 wires that powers the motor. I cleaned it (I will try to find a replacement connector) and I tried to power the drivers one by one, it worked, and now all drivers work.

Sincerely I don't think the problem was because of that imperfect connection on the Y motor wire, the poor connection was not on the + and - cables, but on the ones that connects the motor with the driver, I don't think the Leadshine drivers are that smart, to sense the poor connection on one motor wire, and if they ware I think it should somehow turn the RED led on and stop powering the motor.

Attachment 473066

I don't know yet where the problem came from, but I'm glad the machine is working again.

PS. Regarding the VFD relay, it seems only when I press THE FIRST TIME the START SPINDLE button in path pilot, only than the relay is energized, and when stopping the spindle from path pilot, the relay remains energized for the entire session. I didn't know this, I'm just glad it works.

There is a posibiliity that I purchased a very bad glass fuse lot, the first one I mounted today I noticed (after 1 - 2 hours) when I tried to remove it , that the metal cap can be removed very easily, the wire inside it was conducting current, but when the cap was mounted the fuse didn't work, there was no contact between the metal caps.

The second one, don't know if it was like this from the beginning or the Tormach blown it, as you can see only when I noticed it doesn't work (after another 1 - 2 hours) and removed it from the DC BUS board and tried to remove the metal cap, I could see it's burned inside the metal cap :(

After I installed the third NEW fuse on the DC BUS board, I tried to power on the machine without drivers connected, the DC BUS board turned on, the green led was on, than I connected the drivers one by one, and all worked.

We'll see tomorrow or the next week if the problem persists, it happen for the first time, since 2016, the machine works 6 days a week, around 8 - 12 hours a day, milling 90% tool steel 1.2379.

When the DC BUS board turned ON without drivers connected I suspected that maybe Z driver died (and shorted DC wires, the reason for the blown fuses), and maybe this was the initial reason why my Z axis fall on the stock material yesterday. But it seems the Z driver works, so I'm not 100% convinced that I found the real problem.

Glad you got it fixed.

So far so got, yesterday my Tormach milled from 9 AM to 7PM .. everything was ok, today everything is running normal.

Quote:

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Originally Posted by ovisopa

It seems the new 15A fuse I mounted has burned ! visually there isn't anything wrong with it, but when I tried to remove the metal covers from the glass it clearly shows it was burned.

I noticed that there is something wrong with the new fuse when I tried again to measure the voltage on the fuse (I tried this to be sure the rectifier bridge diode is ok)

https://www.cnczone.com/forums/attac...d=473068&stc=1

After changing it I also removed all drivers connectors, and it seems the Y motor connector, has a darken/burned pin, the PIN was one of the 3 wires that powers the motor. I cleaned it (I will try to find a replacement connector) and I tried to power the drivers one by one, it worked, and now all drivers work.

Sincerely I don't think the problem was because of that imperfect connection on the Y motor wire, the poor connection was not on the + and - cables, but on the ones that connects the motor with the driver, I don't think the Leadshine drivers are that smart, to sense the poor connection on one motor wire, and if they ware I think it should somehow turn the RED led on and stop powering the motor.

https://www.cnczone.com/forums/attac...d=473066&stc=1

I don't know yet where the problem came from, but I'm glad the machine is working again.

PS. Regarding the VFD relay, it seems only when I press THE FIRST TIME the START SPINDLE button in path pilot, only than the relay is energized, and when stopping the spindle from path pilot, the relay remains energized for the entire session. I didn't know this, I'm just glad it works.

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This is a fairly common problem with the stepper drivers, all 3 of mine failed in this manner at different times, it seems the connector isnt large enough to handle the current unless its in perfect condition.

Quote:

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Originally Posted by popspipes

This is a fairly common problem with the stepper drivers, all 3 of mine failed in this manner at different times, it seems the connector isnt large enough to handle the current unless its in perfect condition.

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I winder if replacing those green terminals with a quality brand, like Phoenix, would help?

Quote:

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Originally Posted by MichaelHenry

I winder if replacing those green terminals with a quality brand, like Phoenix, would help?

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I wound up using those push together insulated spade connectors from the hardware to repair mine and no trouble since!

https://www.cnczone.com/forums/attac...d=473310&stc=1https://www.cnczone.com/forums/attac...d=473312&stc=1

Post is a bit screwed up but this is what I did to solve the problem, a bit unorthodox but it works and most likely wont happen again.