3 Phase 220 to 3 Phase 440

[Anthony Spotorno]

I currently have a Phase Perfect 20HP unit to drive all of my 3ph ~ 220v tools. As a 1 man shop, I only run 1 tool + dust collecto.

I am looking at acquiring a Martin Shaper that only offers 3ph ~ 440v on their 7.5HP motor... (I can downgrade to their 5.5hp motor, but would rather have the 7.5)

Is there a way to convert from 3ph ~ 220v to 3ph ~ 440v?

Thanks.

[David Kumm]

Three phase transformer or two ( or three ) single phase step up transformers. Delta to wye isolation is first choice, delta to delta autotransformer is second choice. Dave

[Anthony Spotorno]

IC, so something like a Grainger (Acme Electric) 4WUE6 - 240VAC Delta to 480VAC Wye would work? That transformer is about 2300.00... Just want to make sure before I decide on the shaper, how much more it would cost to have the power issue solved.

[Rod Sheridan]

Anthony, what is the rated full load current of the motor?

The transformer you selected is 15KVA, depending upon the motor nameplate rating I might select a 9KVA transformer.........Rod.

[Anthony Spotorno]

According to Martin the T12 shaper has a 7.5KVA (10HP) option. I'll look at other manuf to see if I can locate a 9KVA unit, might save some on the price.

[J.R. Rutter]

Also, searching used equipment dealers often turns up transformers for a lot less money. I have a 208 to 440 that feeds a sub panel so that multiple machines can be wired up.

[Darcy Warner]

Unless I am desperate, I will never buy a new transformer.

[Jeff Heath]

Second that^^^^ Plenty of good quality used transformers for under $500. The size transformer you need is a very common size, which means they are found surplus, all over the place.

[Chris Hachet]

Unless I am desperate, I will never buy a new transformer.

Again, lots of used stuff available.

[Bill Dufour]

used motor probably no more cost then used transformer of same horsepower.
Bill D.

[Chris Hachet]

used motor probably no more cost then used transformer of same horsepower.
Bill D.

Not to mention a ton simpler.

[David Kumm]

Good luck finding a metric large frame 7.5 hp motor with a shaft long enough to hold multiple sheaves. Probably cheaper to rewind but then you also have to redo the electronics. A used transformer should be under 500. the problem is always finding one close enough that the shipping doesn't kill you. Freight is cheaper now than a year ago so that helps a little. Dave

[Rod Sheridan]

Not to mention a ton simpler.

Except for changing the switches, starter and all the wiring:D

[J.R. Rutter]

used motor probably no more cost then used transformer of same horsepower.
Bill D.

On a Martin? I think I would rather do the transformer. Dead simple to wire, just expensive to ship.

[Philip Hine]

Another possibility would be to get a dual voltage motor. If the motor that comes on the machine is a 9 lead motor it can be configured for the lower voltage.

Phil

[Joe Calhoon]

Not possible on that machine. Inverters and a lot of other electronics going on. They used to offer it 220 but had issues at the lower voltage.

[Anthony Spotorno]

Been searching for transformers, but only one I seem to find is the 15kva Acme unit from Grainger. Might be overkill... a 9 - 10kva unit might be better. Do not know if there are any advantages / disadvantages to overpowering the transformer?

The motor is 7.5kva and the feeder is also 440v as well so have to consider that additional power requirement along with the accessories on the Martin shaper.

[David Kumm]

Doubling the motor kva is not considered to greatly oversize the transformer. The machine likely has a soft start but harder starting machines need to have a transformer oversized. I have a 240-480 15 kva and would not want a smaller one. Machines typically have 5-12 hp motors in three phase so you have it covered. I'm surprised you can't find a use one here in US though. Dave