[juanswart101]

Hi Guys,

Hope you can help me out here.

I have the PCNC1100. Once in a while, not every time, I get a power trip and an error message on my VFD when I engage my spindle, in auto or manual, high speed or low speed.
The power trips at the DB board so everything shuts down. The only error I see is on the VFD, it says "tr uv" which means tr = trip and uv = undervoltage.
My input voltage is fine. I figured that the error has to do with the VFD.

Evertyhing else works fine, I can move all three axises at the same time but when I engage the spindle it trips the power.

I had the error before but I couldn't find anything wrong at the time. Hours later the error disappeared and the machine worked fine again for weeks.
Today it started again.

Have any of you experienced this error before and what can cause this??

Any advise would be appreciated.

Regards
Juan
South Africa

[soofle616]

I assume you're replacing a fuse or resetting a breaker when this happens? If so, it sounds like there is too much surge current when the motor starts up causing the trip. The VFD is simply saying that it doesn't have enough input power which makes sense if the power was interrupted. This could be a vfd going bad or the spindle motor. As for where to start, I can't help you there other than a guess and check approach but hopefully someone else has a better method to determine the faulty component. I would tend to suspect the motor over the vfd since the motor is the thing doing the physical work and therefore subject to mechanical wear over time.

[popspipes]

I had this problem a few years back, it was caused by starting the bandsaw while the 1100 was running, this caused a bit of a voltage drop on one leg of the 230v input to the machine and was enough to trip the vfd.

[shred]

I had this problem a few years back, it was caused by starting the bandsaw while the 1100 was running, this caused a bit of a voltage drop on one leg of the 230v input to the machine and was enough to trip the vfd.

I've seen errors starting a welder too, and with GFI circuits, but unless the main fuses are blowing, other things in the system should be powered as the VFD gets power upstream of everything else..

[machinehop5]

...could be as simple as a loose wire Lug on the incoming power side. Not at the machine but, maybe loose wire in your main Breaker Box

[juanswart101]

Hi Guys,

Thanks everyone for there input.

@soofle616, you are the closest. I have disconnected the VFD and it did not tripped, then reconnected the VFD and disconnected the motor and still all was good. I then disconnected my eath from the machine and reconnected the spindle motor to the VFD and everything still worked. So motor starts and spins in all availble options.

I now need to check my wires between the VFD and the spindle motor, hopefully it is not the spindle motor ??

@ popspipes and shred, I made sure the power was sorted and that there were no other power interruptions while sorting out this issue. But will keep that in mind before welding or doing something else whilst miling.
@ machinehop5, checking wires and lugs was the first thing I did more than a year ago when this problem started. But one needs to be sure so I did check again.

I now have an ATC issue, It is not referencing and gives me an ATC I/O failure error. I have replaced the USB cable that got damaged and arced through to the body.
I perhaps need to do an updaed on pathpilot cause my software is very old.
I have opened a new thread for the ATC I/O failure, but if you know where to start, please advice.

Will be working on the ATC tonight. Once done I will look for the earthing issue.

Cheers
Juan


Thanks for the advice.

[shred]

Hi Guys,

Thanks everyone for there input.

@soofle616, you are the closest. I have disconnected the VFD and it did not tripped, then reconnected the VFD and disconnected the motor and still all was good. I then disconnected my eath from the machine and reconnected the spindle motor to the VFD and everything still worked. So motor starts and spins in all availble options.

I now need to check my wires between the VFD and the spindle motor, hopefully it is not the spindle motor ??

@ popspipes and shred, I made sure the power was sorted and that there were no other power interruptions while sorting out this issue. But will keep that in mind before welding or doing something else whilst miling.
@ machinehop5, checking wires and lugs was the first thing I did more than a year ago when this problem started. But one needs to be sure so I did check again.

I now have an ATC issue, It is not referencing and gives me an ATC I/O failure error. I have replaced the USB cable that got damaged and arced through to the body.
I perhaps need to do an updaed on pathpilot cause my software is very old.
I have opened a new thread for the ATC I/O failure, but if you know where to start, please advice.

Will be working on the ATC tonight. Once done I will look for the earthing issue.

Cheers
Juan


Thanks for the advice.

How old is your ATC? The earliest ATC boards (the one by the air solenoids) had a mechanical relay on them that could bounce open under certain circumstances (lots of chatter in my case), which would cause an immediate power cut to the VFD. It was replaced with a solid state relay in later board revisions. Likely not your problem but maybe worth sending Tormach the part number as a check if your ATC is from the first batch.