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Discussion Starter · #1 · (Edited)
I had a client text me last night and he wants a wood shop tool connected. He insists I need to supply him with 200 amps at 3 phase.., it's a small-ish hand tool from Europe as I understand from the texts discussion had so far.

Not being totally up on my European power needs but I should be able to hook this guy up to 208V? Some wattage and amp draws may change but it should run close to what it was designed at, right?

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It’s going to run faster on 60 HZ than the 50 HZ it was designed for. It wants 240 so at 208 she’s going to run hot. At 2200 watts their voltage & frequency probably a 25 amp 2-pole breaker.
 

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If he wants a 200 amp service install it.
At 208v it would be fine because it is looking for 220 Volts.
As @LGLS said it will be fast at 60hz and since it is 2800 RPM it may exceed the balance point of the motor.
You don't show if it is single or three phase. If three phase run it off of an invertor and set max freq and voltage as per nameplate.
 

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Discussion Starter · #4 ·
If he wants a 200 amp service install it.
At 208v it would be fine because it is looking for 220 Volts.
As @LGLS said it will be fast at 60hz and since it is 2800 RPM it may exceed the balance point of the motor.
You don't show if it is single or three phase. If three phase run it off of an invertor and set max freq and voltage as per nameplate.
Yea, I asked about single or three and he says three, I'll have a look for myself later. The nameplate was all I got and couldn't tell but thought three-phase handle tool sounds intense. Maybe the S3 on the nameplate is supposed to be an indicator.

He was asking for 200 amps to the tool, that I don't think I should do. If he wants a new 200 amp shop service, that I'd be happy to do.
 

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Yea, I asked about single or three and he says three, I'll have a look for myself later. The nameplate was all I got and couldn't tell but thought three-phase handle tool sounds intense. Maybe the S3 on the nameplate is supposed to be an indicator.

He was asking for 200 amps to the tool, that I don't think I should do. If he wants a new 200 amp shop service, that I'd be happy to do.
You haven’t laid eyes on it yet. There’s no way anything requiring 200 A at three phases is a handheld tool. But now you know what kind of customer you have. Charge large. $$$$$ (y)
 
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Discussion Starter · #6 ·
You haven’t laid eyes on it yet. There’s no way anything requiring 200 A at three phases is a handheld tool. But now you know what kind of customer you have. Charge large. $$$$$ (y)
I haven't seen it. I told him that 200 amps for a hand tool was crazy and dangerous, bound to ruin life and limb and tool.
 

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I haven't seen it. I told him that 200 amps for a hand tool was crazy and dangerous, bound to ruin life and limb and tool.
You talk too much. :whistle:
 
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Discussion Starter · #11 ·
Pass on the job and save yourself a lot of headache from this customer
I have tried, and succeeded but sometimes they keep coming back.

Longer story. I do maintenance for several buildings, they rent small bays to small business. I often get referred by the owners, my clients, when a new tenant moves in and they need some electrical work done. I do what I can but sometimes it's frustrating. I feel some ownership of the place and I feel like I owe the owners that the place stays in good working order, sometimes it is difficult.

Label has watts, amps and volts.
That was the first thing I pointed out, guess it isn't as obvious to some people.
 

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watts suggests its 3 phase
How so? I can clue you into one little fact toyed… Every premise every home and every building in Germany has three phase power. And it looks like that’s a German machine. I don’t know what Germany was thinking a residence needed three phases for but… Since it’s everywhere, it stands to reason that Even the small hand tools would utilize it.
 

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Discussion Starter · #15 ·
watts suggests its 3 phase
How so? I can clue you into one little fact toyed… Every premise every home and every building in Germany has three phase power. And it looks like that’s a German machine. I don’t know what Germany was thinking a residence needed three phases for but… Since it’s everywhere, it stands to reason that Even the small hand tools would utilize it.
Now I would like to know more.
 

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After a brief search it appears as a motor for a portable chain saw mortiser, an old one at that. The motor tag appears to be for a 3 phase machine, based on the dual voltage, dual amperage, and wattage rating. The wattage calculates out closely with with a 3 phase supply at the voltages listed.

For 3Φ amps, 2200W / (230V x 1.732) = 5.52A, power factor not included. For 1Φ amps 2200W / 230V = 9.56A, with the nameplate value of 6.5A it's clearly not 1Φ

For a 60Hz power supply connection it would be best connected to a 240V 3Φ system instead of a 208V system, based on the V/Hz that the motor was designed to run on.
230V / 50Hz = 4.6 V/Hz.
240V / 60Hz = 4 V/Hz
208V / 60Hz = 3.46 V/Hz, could cause motor overheating if run at the full load.

RPM will be higher as noted earlier. 20% Higher. 60/50 Hz = 1.2 multiplier
2200 RPM x 1.2 = 3360 RPM motor output. 3600 RPM is normally not a problem for 2 pole motors, but with an open chain mortiser you don't want to be operating it with a worn chain blade. I have no idea what the gear ratio is to the chain blade, or the blade speed, your customer should check with the manufacturer to see if the blade speed would be acceptable with the higher motor RPM.

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After a brief search it appears as a motor for a portable chain saw mortiser, an old one at that. The motor tag appears to be for a 3 phase machine, based on the dual voltage, dual amperage, and wattage rating. The wattage calculates out closely with with a 3 phase supply at the voltages listed.

For 3Φ amps, 2200W / (230V x 1.732) = 5.52A, power factor not included. For 1Φ amps 2200W / 230V = 9.56A, with the nameplate value of 6.5A it's clearly not 1Φ

For a 60Hz power supply connection it would be best connected to a 240V 3Φ system instead of a 208V system, based on the V/Hz that the motor was designed to run on.
230V / 50Hz = 4.6 V/Hz.
240V / 60Hz = 4 V/Hz
208V / 60Hz = 3.46 V/Hz, could cause motor overheating if run at the full load.

RPM will be higher as noted earlier. 20% Higher. 60/50 Hz = 1.2 multiplier
2200 RPM x 1.2 = 3360 RPM motor output. 3600 RPM is normally not a problem for 2 pole motors, but with an open chain mortiser you don't want to be operating it with a worn chain blade. I have no idea what the gear ratio is to the chain blade, or the blade speed, your customer should check with the manufacturer to see if the blade speed would be acceptable with the higher motor RPM.

View attachment 165243
On imported saws normally you have to go to a lower pitch (teeth per inch) which is a simple change. On arbor saws at lumber mills they often do this just to get maximum production out of hard woods vs soft woods.
 

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208V / 60Hz = 3.46 V/Hz, could cause motor overheating if run at the full load.

RPM will be higher as noted earlier. 20% Higher. 60/50 Hz = 1.2 multiplier
2200 RPM x 1.2 = 3360 RPM motor output. 3600 RPM is normally not a problem for 2 pole motors, but with an open chain mortiser you don't want to be operating it with a worn chain blade. I have no idea what the gear ratio is to the chain blade, or the blade speed, your customer should check with the manufacturer to see if the blade speed would be acceptable with the higher motor RPM.
Excellent post (although the base motor speed was 2800RPM, not 2200, so the new speed will be 3360).

Just to add on to the motor over heating issue: The lower V/Hz ratio will result in less torque, in this case 75% of rated torque, which means to do the same work, it will slow the motor down, increase the slip, which will draw more current, thus heating up the motor more. In addition, the PEAK torque, which is what a motor uses to RE-accelerate after a load is added, will drop at the SQUARE of that difference, so the PEAK torque will drop to just 57% of the rated peak torque capability. Typical PEAK torque (Break Down Torque) is 200-220% of Full Load Torque, so in this case you will only see maybe 125% of rated torque as peak torque. That then means that the motor will more easily stall when you plunge into a work piece.

That motor is also carrying a Duty Cycle rating of "S3 40%" (on the left side of the plate). S3 means it is rated for "periodic" use, the 40% is the amount of time it can run as opposed to rest. So that means if you run it for 60 seconds, it must rest for 60% of the time, or 1.5x the amount of run time, so the rest period must be at least 90 seconds before you can run it again. Given the added heating issues, I would advise the user to probably double that at the very least.

To get rated performance from that motor, you would need to do one of two things;
1. Get a buck-boost transformer to boost the 208V up to around 276V, but that will still leave you with the possible blade speed issues.
2. Boost the voltage to 220V and get a VFD, then program the VFD to 50Hz.
 
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With the VFD you don’t need to use a transformer. The VFD is capable of giving you the voltage boost too. You just enter the name plate data as is.

I think that torque is a huge issue and here is why. That motor is 6.8% slip (200 RPM divided by synchronous of 3000 RPM). Even very old motors back in the U frame days may have high starting current but still have around 3% slip. Also that’s duty cycle is very low. This all points towards a tool is meant for high peak torque, even outright stalling out in the work piece, without damage. This is typical of saws and the duty cycle is never an issue. I’ve set up a lot of saws and chip mills of the industrial variety. The overload relay is there for Code. The overcurrent/stall relays are what gets used.

You could go VFD. The rating is a bit tricky for this application. Going by heavy duty rating we need about 400% of name plate for stall or 6.3 x 4 or 25.2 A for 40% of the time. VFDs are rated with a peak and continuous cycle. The peak cycle is always max output for 30 seconds. So from this catalog:


Expect to pay about 60% of list as a retail price. Be Using this example because they publish their list prices. Ok so if it is going to be eating dust I suggest buying a “wash down” duty drive. These are sealed typically to NEMA 4X so dust is a non-issue. So if this is the case the SWs are rated for “heavy duty” at 150% of current for 1 minute. So dividing 25.2 A by 150% we get 16.8 A. It’s just slightly undersized but I’d look at the 16 A SW for $1458 list. If you can keep it in clean air another option with a nicer display is the newest H2. The smallest at $1351 with a conduit box listed for $47 does it. You could also go flange mount providing your own enclosure for $141 list but when all is said and done it’s pointless to do this. Also need a fused disconnect for about $100 street price and guessing $100 in conduit. So parts only retail price is around $1100.

Plus you are dealing with an old used motor with unknown life left. But it can be rewound for probably $1000.

It is probably going to be vastly cheaper and better to simply buy a 208 V 60 Hz motor even if it needs machining to fit. That is cheaper by quite a bit than the VFD as long as it’s not excessively frankensteined. Plus it’s new so you get long life and more torque. Work with a motor shop that specializes in this. Or just buy a new tool.
 
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