# 1 to 3 phase static convertor, 1-3 HP



## Bi11Hudson (Mar 12, 2020)

Looking for something else, I found this on eBay. Although used, it is going for a fair price. USA made, Min 1 HP load, Max 3 HP load. Has a few days to run. Looking at the for sale list, the guy is a seller not particularly knowledgable of what he is selling.








						PAM-300 1-3 HP - 220 VAC - PHASE-A-MATIC PHASE CONVERTER  | eBay
					

Find many great new & used options and get the best deals for PAM-300 1-3 HP - 220 VAC - PHASE-A-MATIC PHASE CONVERTER at the best online prices at eBay! Free shipping for many products!



					www.ebay.com
				




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## cathead (Mar 12, 2020)

I have two of those.  I used one for years on my vertical mill until I got a VFD.  The other one is being used on my Springfield lathe currently.  
They work OK but do not generate full horsepower.  I took one apart once to see what is in the box and all that is in there is
a couple capacitors.  If it were me, I would put my money on a VFD.  I will have to say though that mine have been very dependable.   
My spare Phase-A-Matic is still mounted on the ceiling in the shop I think.  I will have to look for it this morning.  The E-Bay listing
is a MAKE OFFER so it might be a good deal at the right price.  If you require full horsepower, Bill, an RPC or VFD would be a better choice. 
On the other hand, it is a simple hook up,small, light weight, quiet and portable, so they have their good points too.


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## projectnut (Mar 12, 2020)

I have a total of 4 static converters running machines in the shop.  They range from 1/3hp to 3 hp.  Only 1 of the converters is a Phase A Matic.  The others are American Rotary (now sold under their subsidiary as North American Phase Converter Co.).  The Phase A Matic has been on the mill for nearly 20 years.  Per advise from the company I purchased the 300HD model.  According to the company it's a better choice for a machine that is instantly reversed.  Since I do quite a bit of power tapping I took their advise and have been more than satisfied.

The downside of a static converter is that the machine will only generate about 2/3 its rated hp.  A static converter is only a series of capacitors that generates the 3rd phase until the motor comes up to speed.  Then the 3rd phase drops out  and the motor runs on single phase.  I have heard stories about the "possibility" of 3 phase motors overheating when run on single phase, but have never experienced it.  I use many of the machines for hours at a time and have never felt a motor more than warm to the touch.

When looking into using VFD's rather than static converters I chose the static converters for a couple reasons.  Even though the power output is less with a static converter I have never been in a situation where I required more hp than the machine could generate.  Using static converters also allowed me to retain the original machine controls.  In at least 2 cases (1 mill and 1 lathe) the speed controls are integral in the machine control panel.  With the introduction of a VFD those functions would have had to be transferred to the VFD.

Several years ago I purchased a 15 hp rotary converter with one of my machines.  The original plan was to replace all the statics with the single rotary.  I had an additional sub panel installed to power it a couple years ago, but that's as far as it went.  The converter control panel is still sitting under the bench, and the idler motor is still in the carton on the shelf.  At this point I don't see making the changeover anytime in the near future.  All the machines run fine with their current configuration.  Maybe I'm just getting old and/or lazy, but for the time being I'd rather just go to the shop and use the machines rather than spend weeks rewiring everything just to have them run the same way they've been running for years.  If something changes where I feel it's appropriate to install the rotary converter I'll do it, but for now I'll leave well enough alone, and just make chips.

As for Phase A Matic they are probably the Cadillac of the industry.  They are dependable, and do seem to last indefinitely, but are probably the most expensive on the market.  The 300HD model today sells for around $310.00.   A similar size North American converter sells for around $100.00.  In my experience both are good products.


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## benmychree (Mar 12, 2020)

I used a Phase A Matic to build a rotary converter out of a 5 HP 3 phase motor, just added a bank of oil filled capacitors to balance the voltage coming out; it powers all the equipment in my shop.


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## MrWhoopee (Mar 12, 2020)

That unit is comparably priced to the WNY unit currently on sale.








						WNY Supply online store for static & rotary phase converter
					





					phaseconverterusa.com
				




I mistakenly purchased a 3/4-5 Hp unit








						MAC05-3/4 - 5Hp HD MAC Static phase converter
					





					phaseconverterusa.com
				




Unfortunately, my mill is 2 Hp while my lathe is 1 Hp and the switch settings need to be different for the two. Instead of changing the settings, I just turn on the mill and let it function as an RPC when I'm using the lathe. I'm tempted to to get a 1-3 Hp unit to eliminate this.


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## BGHansen (Mar 12, 2020)

I have a Phase A Matic on a 2HP Bridgeport.  Works fine for me, never stalled the motor at the paltry 1.33HP it's putting out because of the 1/3 reduction.  I figured belt drive BP's use a 1 HP motor, so my 2 HP running a 1.33 HP should be fine.  The mill has had that same converter on it for over 30 years without any issues.

Bruce


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## ELHEAD (Mar 13, 2020)

Bought a WNY several yrs. ago. For 5 HP Stephen A. Bader 132 " belt sander. Works great. Power loss is probably insignificant, as 5 HP is far more power than needed for my use. I do recommend WNY, but I have never used another.
Dave


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## Karl_T (Mar 13, 2020)

I bought a phase a matic 25 years ago and hooked it to an idler motor. Been trouble free the whole time.


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## JimDawson (Mar 13, 2020)

I've had a phase a matic on my 3HP Jet lathe for the last 25 years or so.  Has been working fine.  I've thought about installing a VFD, but I can't figure out why I need one.


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## Bi11Hudson (Mar 13, 2020)

Just to keep things in perspective, I have no intention of purchasing this for myself. I posted it so someone that was looking for 3 phase conversion might have a go. I have small machines and the work I do makes single phase equipment perfectly satisfactory. A large factor for my small(?) machines is weight, a wood frame building can take only so much.

As to price(!), I am familiar with sand cast transformers and the price is approximately comparable to a new "16-32 volt buck-boost' of the same physical design. I was not aware that VFD drives could be had so inexpensively.

If it came down to one or the other, I am an "old school" electrician and would choose the transformer over the VFD any day. For the reasons stated above;



projectnut said:


> When looking into using VFD's rather than static converters I chose the static converters for a couple reasons.  Even though the power output is less with a static converter I have never been in a situation where I required more hp than the machine could generate.  Using static converters also allowed me to retain the original machine controls.  In at least 2 cases (1 mill and 1 lathe) the speed controls are integral in the machine control panel.  With the introduction of a VFD those functions would have had to be transferred to the VFD.
> ~            ~            ~            ~            ~            ~            ~            ~            ~            ~            ~
> As for Phase A Matic they are probably the Cadillac of the industry.  They are dependable, and do seem to last indefinitely, but are probably the most expensive on the market.  The 300HD model today sells for around $310.00.   A similar size North American converter sells for around $100.00.  In my experience both are good products.


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## cathead (Mar 13, 2020)

Just for the record, I purchased my VFD when the two speed switch wore out on my Enco 9x42 vertical mill.  The cost of the switch
was about the same as the VFD so thought I would give high technology electronics a try.   My mill motor has two speeds
and the switch had both forward and reverse on it, so quite a complicated affair.  I was not in the mood to replace that switch with another
of the same as they seemed to me to be of relatively poor quality and basically not repairable.  Not I'm not terribly fond of glorified
switching mode power supplies which is what a VFD is, however for my application is has been the perfect solution.  So in retrospect
the hi-tech VFD has it's place I guess and if it fails, I would buy another one.  I like big heavy transformers, solid state bridge rectifiers and analog
dials too but there comes a time when one has to admit that advances in technology can be a good thing.  I really have enjoyed the improvement
of my step pulley mill to variable speed.  The pulley has been set on 850 rpm for years now and I have no need to change it.  I  have to agree with 
Jim Dawson that a VFD on a lathe would be somewhat ambiguous.


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## ttabbal (Mar 13, 2020)

You could probably make a VFD with tubes and transformers... You might have to make the tubes though...


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