Question regarding Powermatic 3520A..
#11
  
Been lurking for years here and finally joined. My apologies for my first post being a question.. I'm not new to woodworking but am new to turning. Irecently purchased a PM 3520A for $1000. I couldn't turn it on to test when I bought it because the garage it was in didnt have 220. I didnt realize until I got home that it has a small breaker box mounted to it underneath the motor. Theres a small hole cutout in the faceplate too which is a little weird. My best guess is it's for VFD  protection from power surges but really I just want to make sure it's safe to turn on and use. Can anyone give me more details? Any help is appreciated.
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#12
  Re: Question regarding Powermatic 3520A.. by Kingsroots (Been lurking for yea...)
First, welcome. No problem with having your first post be a question.

Your description has me worried. It has been a while since I saw a 3520A in the shop of one of the local turning club members.

Have you checked the manual to be sure that you got all of a PM3520A ?

Does it look like the VFD has an RPM readout?

Can you post a pic of the control panel?
"the most important safety feature on any tool is the one between your ears." - Ken Vick

A wish for you all:  May you keep buying green bananas.
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#13
  Re: Question regarding Powermatic 3520A.. by Kingsroots (Been lurking for yea...)
Thanks for responding. I'll try to post some pics hopefully it works lol.

   
   
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#14
  Re: Question regarding Powermatic 3520A.. by Kingsroots (Been lurking for yea...)
Here's another..

   
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#15
  Re: Question regarding Powermatic 3520A.. by Kingsroots (Been lurking for yea...)
I miss-read your first post to think that the hole in the faceplate was in the lathe faceplate.

The breaker box looks like it is intended as a way to disconnect the lathe from the power feed at the end of the day.

That sounds like a reasonable alternative to unplugging the lathe and a lot cheaper that installing a power on/off switch at the wall receptacle.

That hole cut in the faceplate for access to the breaker screw is definitely odd. It is also odd to have 2 different breakers for the 2 phases of the 220V/240V.

Hopefully, a better electrician and VFD person will come along with advice.

I do not know what might happen to a VFD if it loses just one phase of its power feed.

In the mean time, it wouldn't hurt to (with the machine not plugged in) open the breaker box face plate and take (and post) another pic from roughly the same viewpoint as the one showing that cutout.

It does look like the person who did it had their act together enough to make the cord from the breaker box to the VFD long enough to slide the headstock as far away as you might want it for turning at the end.

It sounds like you got a great deal if everything works right.
"the most important safety feature on any tool is the one between your ears." - Ken Vick

A wish for you all:  May you keep buying green bananas.
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#16
  Re: Question regarding Powermatic 3520A.. by Kingsroots (Been lurking for yea...)
Ok that makes sense to have it as a shutoff instead of unplugging. The cutout on the faceplate is my concern too I'm not sure why that was done. I'll take the faceplate off and take a picture tomorrow and post. I also agree that having 2 separate breakers seems odd. I'm far from an electrician but I would think having a double is the way to go.
 The previous owner was selling this for his late father who used it only a handful of times apparently. He purchased it from a woodworker and I guess never asked about the breaker box. I was told it ran without problems but I'm not sure yet and you never know. Still, for the price I couldn't turn it down.
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#17
  Re: RE: Question regarding Powermatic 3520A.. by Kingsroots (Ok that makes sense ...)
(02-06-2021, 04:10 AM)Kingsroots Wrote: Ok that makes sense to have it as a shutoff instead of unplugging. The cutout on the faceplate is my concern too I'm not sure why that was done. I'll take the faceplate off and take a picture tomorrow and post. I also agree that having 2 separate breakers seems odd. I'm far from an electrician but I would think having a double is the way to go.
 The previous owner was selling this for his late father who used it only a handful of times apparently. He purchased it from a woodworker and I guess never asked about the breaker box. I was told it ran without problems but I'm not sure yet and you never know. Still, for the price I couldn't turn it down.

Breaker to isolate the machine at the end of the day makes some sense--though it seems the breakers should have been tied together.  Wondering if a prior owner may have opened that hole to run a 120v outlet for a lamp/light of some sort. Just kind of guessing, partly based on some of the odd wiring we found the basement of our house when we bought it!!
earl
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#18
  Re: Question regarding Powermatic 3520A.. by Kingsroots (Been lurking for yea...)
I would cover the hole with a piece of plastic or something. Also at minimum tie the two breaker handles together. I would change it out to a two pole breaker, they are fairly cheap.
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#19
  Re: RE: Question regarding Powermatic 3520A.. by iclark (I miss-read your fir...)
(02-06-2021, 03:41 AM)iclark Wrote: I do not know what might happen to a VFD if it loses just one phase of its power feed.

It’ll just shut off.  The circuit will be broken, and though it’s unusual to break one leg of a 240V circuit on a 120/240V split-phase system, it will shut the load off just as well as opening both poles, same as a 120V circuit.

But the OP should stick a 2-pole breaker in there.  

https://www.homedepot.com/p/Square-D-QO-.../100032386

Or at least a handle tie.

https://www.homedepot.com/p/Square-D-QO-.../100165878

And cover that hole.  Can’t do it from behind, since the top of the normal slot is what holds the breaker in place and anything on the back of the cover would make it stand out.  But a piece of plastic or metal with a couple of screws, or just glue, would at least protect against someone sticking something in there.  

A 2-pole breaker would be held in place by the other slot, since that wasn’t cut away, which tilts the fix in favor of replacing those two with a single breaker.
Tom

“This place smells like that odd combo of flop sweat, hopelessness, aaaand feet.”







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#20
  Re: Question regarding Powermatic 3520A.. by Kingsroots (Been lurking for yea...)
Thanks everyone that responded so quickly. I think I'll replace the single breakers with a 2 pole like suggested and see if I can either buy a replacement cover or just glue a piece over the cutout. Hopefully this thing starts up fine with no issues (crossing fingers).
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