# PowerFlex 40 Intermittently powers down



## BIG J Sparky (4 mo ago)

I have a PowerFlex 40 2hp VFD that powers down and then back up when a remote start button is pushed, acts if you broke the line power. No faults. Going to replace the drive, just curious if anyone knows why this would do this???


----------



## Almost Retired (Sep 14, 2021)

these guys might be able to help
@gpop 
@micromind


----------



## paulengr (Oct 8, 2017)

Sounds like power supply is failing and when you close contacts on an input you are drawing it down so far it reboots. Maybe the input is going bad? Try another one..

PF40s were great for their time. Discontinued so AB will offer the 525.


----------



## gpop (May 14, 2018)

I have seen a drive do it but i am not sure why. Maybe the caps or pre-charge circuit / power supply has failed. 

On a large drive that could possible be repaired it might be worth troubleshooting but on a small drive its not financially worth the effort. Unfortunately the 525 are in short supply with hi lead times so you might be stuck unless you are willing to buy new old stock which comes with its own risks.


----------



## JRaef (Mar 23, 2009)

Some PF 40s were made during the so-called "capacitor plague" in which a major supplier of capacitors stole the magic formula for making them from a competitor, but stole the wrong one, so they ended up making billions of bad caps that got out into industry, costing electronics mfrs billions. In the case of the PF40s, some of those caps ended up on the power supply board of the drives and although there was no recall because they lasted longer than most of the ones affected by the plague, they are now way beyond warranty but are failing. There really isn't a fix for it, the caps are surface mounted onto the board.

The PF40 is being obsoleted next month, so if you don't want to change out to a newer PF520, you had better try to find one right now. But good luck with that in this "no parts to build them" world we live in at the moment.


----------



## paulengr (Oct 8, 2017)

JRaef said:


> Some PF 40s were made during the so-called "capacitor plague" in which a major supplier of capacitors stole the magic formula for making them from a competitor, but stole the wrong one, so they ended up making billions of bad caps that got out into industry, costing electronics mfrs billions. In the case of the PF40s, some of those caps ended up on the power supply board of the drives and although there was no recall because they lasted longer than most of the ones affected by the plague, they are now way beyond warranty but are failing. There really isn't a fix for it, the caps are surface mounted onto the board.
> 
> The PF40 is being obsoleted next month, so if you don't want to change out to a newer PF520, you had better try to find one right now. But good luck with that in this "no parts to build them" world we live in at the moment.


All manufacturers are dealing with the same problem but not all are equal. Shop around. I can still get drives but many manufacturers are 3-6 months back ordered. Many retailers got tired of this game too and started carrying inventory where at one time only the stocking distributors did, or you need access to the inventory so that you can see that say the 20s are out but the 25s are in stock. So right now when I do a VFD estimate we usually offer two prices, what is available in stock and what they asked for. The tricky part is the we often have to put the “in stock” quote in terms if “as of today” because tomorrow it can be sold out.


----------



## BIG J Sparky (4 mo ago)

gpop said:


> I have seen a drive do it but i am not sure why. Maybe the caps or pre-charge circuit / power supply has failed.
> 
> On a large drive that could possible be repaired it might be worth troubleshooting but on a small drive its not financially worth the effort. Unfortunately the 525 are in short supply with hi lead times so you might be stuck unless you are willing to buy new old stock which comes with its own risks.


Good to know, good thing we have about (12) 525's on the shelf at the moment. Thank You!


----------

