Running a Hypertherm Plasma on an RPC...

[PlasmaDon]

I just heard back from tech support, they usually are great.
I asked if they have issued a tech bulletin on using a plasma power supply on a Rotary Phase Converter,
'as I have an older transformer as a newer 1650 inverter that I am planning on changing out to.

Answer is no, we don't recommend it, for any type of supply. Period, end of sentence.

Now they have to realize there are many small shops all around the world with only single phase power,
And that some have done this (I am doing it successfully on a max100 transformer type, and did test the 1650
with a hand torch as well)

Haas machine tools realize this, and have work arounds and recommendations.

[weldguy]

I can completely understand why they don't recommend it, I am sure it would open the floodgates to all kinds of new issues if they were to state that it will work. It likely will be just fine as you have found out for yourself, they just don't want to tell you YES it will work work and when a problem arises have you call back for tech support on a power supply issue they have nothing to do with.

[adbuch]

https://www.plasmaspider.com/viewtopic.php?t=33045

[tcaudle]

As weldguy says when you recommend something you end up owning it. Not all RPC are created the same and most do not handle surges real well. There are tricks to take care of that but they go past what a plasma vendor can recommend or support.

I know of shops that are running all the way up to max200 on a RPC but its oversized and expensive .

Our shop is in a rural area and nearest 3P is over 5 miles away. We have no choice but to run RPC on our 3P HAAS VFD , Femoc CNC lathe , 5ft metal shear and a brake press. We were careful to match the converters to the loads buy setting up a digital voltage and current probes on each leg to make sure the caps were correct . While it would not be as critical for a transformer type load most plasma units are not transformer connected . they are switching power sources and most have PFC (Power Facto Correction) that cam mess with the higher impedance lines out of the RPC. We use "pony" motors that act as energy storage devices and also help stabilize the third leg .

[PlasmaDon]

Tcaudle...thank You for this ^^^^
I made my 40 hp 15 years ago, have many hours on it running a 10 hp compressor, some screw machines, a radial drill, etc.
i step it up to 480 vac for some machines. Usually one at time though.
It runs the old Max100 just fine, and I bought the powermax 1650 a few months ago after reading (on here) that they can
handle an RPC, to upgrade my table.

I have been thinking on these higher power RPC's of adding the balance caps's at each machine to alleviate the problem
of a lightly loaded RPC having too high of a voltage on l3.

[adbuch]

I've been running my Hypertherm 85 on a 30HP cnc rotary phase converter for about 8 years now with no problems. This phase converter is sized large to accommodate all of my 3 phase cnc machining centers and conventional 3 phase equipment out in the shop.

David