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200 vs 220 v10/4
Recently acquired a nice Oliver 270-D ina trade with the friend. My original intention was to sell it (happy with my PM 72 as a production saw) but the market for these saws is really soft right now so I may well be keeping it.
My question goes to the 200 v 5 hp 3 phase motor. Some maintain that running the motor intermittently at a higher (nominal 220) voltage won't do any harm. Otehrs say it's always a bad move. Rewinding the motor will be pricey ($600) and used 3 phase buck transformers are pretty uncommon, likely because some don't consider them necessary. What's the best approach on a limited budget? Appreciate thoughts from anyone who's been down this road.
You could consider using a vfd,ac drive.with that you could regulate the output voltage.Factorymation.com sells them,just make sure the one you buy you can adjust the output voltage.Like there model 7300
This is just my opinion so take it for what little it's worth;>) If a motor rewind costs $600 I would run it at your voltage for as long as it lasts. Then if it finally goes spend that money on a new motor that runs the right voltage.
I've been told in the past that as long as your within 10% of the motors rated voltage it's acceptable. In my case though it's for an 208V Omga miter saw which runs intermittently. Been using it for some 6 or more years now without any ill effects. Could be different if your running for hours though?
Thanks for the input. Jeff' s apprach is the same recommended by the motor tech, namely run it on the higher voltage and see what happens. If/when it fries there's really no downside since the old windings have to be cooked off anyhow. That's probably what I'll do. Given that the saw will be used intermittently, it could well last a while like Jeff's RAS. Hope the same can be said for the electric brake. Regardless, one option that will be out is changing the motor. Olivers are direct drive and use an oddball 600 series frame motor.
I have a couple of 208v machines that I've been running on 230v service for about 10 years. No trouble: I can't even remember which machines are which. I know that the PM 66 is 208v, and it runs a lot.
A 20 volt difference is not likely to hurt the motor, but is it really a 20 volt difference? Has the voltage actually been measured at the point of use? Also, what is the operating frequency of the motor? If it was made for a European market it will have a 50 Hz motor. They are not compatible with our 60 Hz power, even if the voltage of the motor matches our North American power.
Please determine your actual point of use
I worked for an importer of European offset printing presses and a significant part of my job was making the European machinery work on US electrical power.
In general motors like higher voltage up to the point that the insulation breaks down on the wiring. 220 vs 200 is not likely to be enough change to impact the insulation unless it was ready to go anyway.
Running a motor at low voltage causes the current to increase, which is far more likely to cause damage.
Given it's a 273 series and the motor is 5hp, it's a 'relatively new' saw. Three-phase is standard so its a question of how it's wired; check the wiring box. If it's wired L-1-7, L-2-8, L-3-9 [3 groups of 3 wires each] it's a 208V wye or star set up. If you have 3 groups of 4 wires it set for 480V. Either should be fine off of your 3-phase power input.
I don't see why you have a voltage concern. Unless the motor has circuitry that derives power by referencing neutral/ground, and I'd bet that your motor does not, then you have no voltage issue. The motor will 'see' only the relationships between the phases, whether the 3-phase configuration is wye or delta.