Penn State Motor question

[Dave38]

Has anyone had their penn state variable speed controller just be at the highest speed right from turn on? Worked foine then all of a sudden, I turned it back on and it ran at the highest speed. The speed control pot is good, and the high and low small pots on the board are not affecting the speed. Any help appreciated.
Dave

 

[Mike Rys]

DId you check the power MOSFET?
I believe the MOSFET part is 1RFP460?

 

[cueman]

It is usually the rotating switch causing that.

 

[Dave38]

DId you check the power MOSFET?
I believe the MOSFET part is 1RFP460?

Just had another controller go down, and seems to be the MOSFETs on both. Just got a 5 pack in. 1RFP250N is the number on mine. I adjusted the High and low speed settings on the board on both of them before they failed. First one ran for 3-4 months and the second one ran for about 2 weeks before failure. Is it coincidence or can adjusting those too much that cause the MOSFETs to fail?

 

[Mike Rys]

I can't see why adjusting the internal pots would cause a premature failure.
When they failed, did you:

Replace them as a pair?
Add thermal compound between the part and the mounting surface?
Buy the parts from a reputable US supplier?

 

[boogieman]

Just had another controller go down, and seems to be the MOSFETs on both. Just got a 5 pack in. 1RFP250N is the number on mine. I adjusted the High and low speed settings on the board on both of them before they failed. First one ran for 3-4 months and the second one ran for about 2 weeks before failure. Is it coincidence or can adjusting those too much that cause the MOSFETs to fail?

Have you had any issues with the power supply or big lightning storms in your area? It does seem very odd that two would go down, I suppose it could be a coincidence.

I'd probably start with looking up the specs of them and probing with a multimeter to make sure they aren't being fed too much power or something. As @Mike Rys said, make sure they have thermal compound, I'd even contemplate putting heat sinks on top of them. They have some copper ones with a thermal pad pre installed, that might be an option.

 

[GoldCrown]

PSI has good customer service

 

[Dave38]

I can't see why adjusting the internal pots would cause a premature failure.
When they failed, did you:

Replace them as a pair?
Add thermal compound between the part and the mounting surface?
Buy the parts from a reputable US supplier?

They have never been replaced until now, up til now they were original. I replaced them yesterday and it didn't change the problems. One was completely dead and the other runs at high speed. The dead one, I found the thermister was way outta specs, replaced it with the one from the other board, and now that one is running. The other one, I found the 5 watt 6.8k ohm resister was open, waiting for replacements before proceeding further.

 

[chuckpilegis]

Have you ever tried KB ? controllers on a taig?