Anyone had to change a pcb in their vfd?

[Bsmith]

After changing some parameters on my cheap vfd, pressed start and motor did half revoloution, blew 13a fuse in plug and tripped mcb. Reset trip, changed fuse, now when I switch on at socket smoke comes from arrowed part in photo, no lc display.
Ali Express say easy repair, they will send me another pcb and I can change them over.
2.2kw output vfd.

 

[minimutly]

Easy enough, provided they send you the board and sub boards attached. Question is though, is the Thyristor block seperate, or part of the board? If it's seperate, and has blown, a new board will go the same way as the old one.

 

[Bsmith]

Easy enough, provided they send you the board and sub boards attached. Question is though, is the Thyristor block seperate, or part of the board? If it's seperate, and has blown, a new board will go the same way as the old one.

What is the Thyrister block? Sorry this is new stuff to me.
This is a new vfd but too old for their useless 30 day warrenty.
I just changed parameter 2 from 0 to 1 hoping it would work with external control switches.

 

[Chippie]

Easy enough, provided they send you the board and sub boards attached. Question is though, is the Thyristor block seperate, or part of the board? If it's seperate, and has blown, a new board will go the same way as the old one.

Not heard of a thyristor block for a vfd….usually 6 igbts for a high power unit or a module for the smaller units….either case…a new board should should have everything to make it sing n dance again..

 

[Bsmith]

So, is it possible to set the parameters to self destruct the vfd or what did I do wrong? I would have thought it would display fault or something on the lcd if I had set it wrong.
I have another 2 vfd's and not had any probs with them.

 

[Robert Weaver]

Arrow looks to be pointing at 2 wire wound resistors soldered in series.
What's parameter 2, is it internal brake?

 

[Bsmith]

Arrow looks to be pointing at 2 wire wound resistors soldered in series.
What's parameter 2, is it internal brake?

Arrow is pointing to some softish gunge that smokes when I turn the power on Robert.
Going by the Chinese English in the instructions book I believed that parameter 2 was to change from panel control on the vfd, to exterior switches, maybe I got it wrong, will attach a photo of parameters tomorrow.
The vfd was fine before I interfered with parameter 2, I changed the acceleration/deceleration times successfully in other parameters.

 

[Pete.]

I think the blue disc is a metal oxide varistor which is there to soak up power spikes. Could be what's gone pop and cooked the resistor pair.

 

[Agroshield]

...parameter 2 was to change from panel control on the vfd

That should not cause it to go wrong. The external control circuit is low voltage, current limited, so in principle you could dead short all of it and it would do no harm.

 

[Bsmith]

I changed parameter PO-02, from 0 to 1, pressed confirm key then pressed run on the vfd, motor turned 180 degrees, fuse in 13amp plug went and tripped the mcb.

 

[Pete.]

Pure co-incidence mate that parameter was not going to affect anything.