[pound]

Hi All,
After investing in an Huanyang HY03D023B VFD ( a 3KW one) a few years ago I finally came to use it. It worked fine several times and I was impressed and then a bang (not while running actually the motor) - no error message but clearly something bad had happened.

Having opened it I noticed a small section of track that connects to the ground terminal (furthest right) had blown out. I check the capaitors the three of them though paralled were fine on the capacitance meter.

Stupidly I decided to repair this track as no obvious damage could be seen elsewhere but at least to my not quite completely stupid strategy I repaired the blown track with fuse wire so that if there was another occurance it would not do too much damaged.

Guess what it blew again (the fuse link I'd installed) clearly something is wrong - well that much was obvious anyway before I tried to repair the board. No error meage appears on the display it thinks everything is fine apparently.

Fortunately no more damage was done trying.

Now to the question.

What is the best components to start checking (given no compnent is visibly damaged) what would cause the ground to carry so much current? Has anybody come across this problem involving the ground path?

P.S I have check for ground loops and run a earth loop test on the mains electrical and that was fine - good earth and low resistance.

[ger21]

Unplug and check the spindle.

[mactec54]

Hi All,
After investing in an Huanyang HY03D023B VFD ( a 3KW one) a few years ago I finally came to use it. It worked fine several times and I was impressed and then a bang (not while running actually the motor) - no error message but clearly something bad had happened.

Having opened it I noticed a small section of track that connects to the ground terminal (furthest right) had blown out. I check the capaitors the three of them though paralled were fine on the capacitance meter.

Stupidly I decided to repair this track as no obvious damage could be seen elsewhere but at least to my not quite completely stupid strategy I repaired the blown track with fuse wire so that if there was another occurance it would not do too much damaged.

Guess what it blew again (the fuse link I'd installed) clearly something is wrong - well that much was obvious anyway before I tried to repair the board. No error meage appears on the display it thinks everything is fine apparently.

Fortunately no more damage was done trying.

Now to the question.

What is the best components to start checking (given no compnent is visibly damaged) what would cause the ground to carry so much current? Has anybody come across this problem involving the ground path?

P.S I have check for ground loops and run a earth loop test on the mains electrical and that was fine - good earth and low resistance.

It sounds like you had a dead short either your wiring is bad or your motor is damaged, what type of motor do you have connected to the VFD Drive

Wire is most likely where the problem is can you take a photo of the wiring

[pound]

It sounds like you had a dead short either your wiring is bad or your motor is damaged, what type of motor do you have connected to the VFD Drive

Wire is most likely where the problem is can you take a photo of the wiring

the motor was not running at the time when the track blew it spun down normally and it happened about 3-4 minutes later while I was preparing to run the motor again.
The wiring must have been alright as when I inspected it after removing there was no shorts but I'll check the motor later anyway just in case the motor has a problem.

The same when I repaired the board it was not running the motor I just powered up the VFD to see what would happen, after 2-3 minutes it blew the track repair that links the groun pin to the pcb.

Not sure if that all gives any clues.

[pound]

what would be usefull is if I knew what has a path to the ground. I would have thought as that should be isolated nothing should in which case what component would fail to give a path ground?

I'll check these IGBT free-wheeling diodes:

https://www.motioncontroltips.com/tr...-power-checks/

If it is a shorted output these might be damaged although elsewhere I've read the VFD is protected against shorts as one would quite imagine but that's no guarentee of course!

[mactec54]

what would be usefull is if I knew what has a path to the ground. I would have thought as that should be isolated nothing should in which case what component would fail to give a path ground?

I'll check these IGBT free-wheeling diodes:

https://www.motioncontroltips.com/tr...-power-checks/

If it is a shorted output these might be damaged although elsewhere I've read the VFD is protected against shorts as one would quite imagine but that's no guarentee of course!

How do you have the input power wired and what are you using single phase or 3 phase to supply the VFD with ,and what voltage

[pound]

How do you have the input power wired and what are you using single phase or 3 phase to supply the VFD with ,and what voltage

its UK so 240 single in to any two terminals RST and 240 3 ph out.

[pound]

what would be usefull is if I knew what has a path to the ground. I would have thought as that should be isolated nothing should in which case what component would fail to give a path ground?

I'll check these IGBT free-wheeling diodes:

https://www.motioncontroltips.com/tr...-power-checks/

If it is a shorted output these might be damaged although elsewhere I've read the VFD is protected against shorts as one would quite imagine but that's no guarentee of course!

checked all that just fine rectifier and IGBT maybe its a VDR just wish I had a repair manual.

[mactec54]

its UK so 240 single in to any two terminals RST and 240 3 ph out.

So you would of connected Live to R and Neutral to T this is the most reliable connection for these VFD Drives

On the outputs the IBGT's get damaged along with the Zener diodes

[pound]

So you would of connected Live to R and Neutral to T this is the most reliable connection for these VFD Drives

On the outputs the IBGT's get damaged along with the Zener diodes

yes that's correct I will try to check the zeners not sure how at the moment (you mean the zeners at the gate of the IBGT) but I think the clue is that current was diverted to the ground and the only components I can see at the moment that route to ground are the VDR's either when faulty or through an overvoltage event.

[mactec54]

yes that's correct I will try to check the zeners not sure how at the moment (you mean the zeners at the gate of the IBGT) but I think the clue is that current was diverted to the ground and the only components I can see at the moment that route to ground are the VDR's either when faulty or through an overvoltage event.

Also check the input current sensors here is an old schematic that may help