Confused BY The Nameplate

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MTW said:
At the top of the label, it is thermally protected.

If the running current in the application is running into the service factor region. You should consider putting a vale in the piping to restrict the flow, and reduce the current draw to the 1.0 SF level for longevity.
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Running into the service factor will reduce life, but it should still not fail in 6 months.
 
Dennis Alwon said:
Here is the rub. My friend is running it on 246V- actual voltage. Every 5 yrs he has to change the pump so I was wondering if this higher voltage is the issue. also why make a pump at 230v instead of 240v which is standard voltage
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How is the motor failing? Is it the windings in the motor? My guess would be no. Is he getting a whole new pump and motor?

Pool pumps lead a tortured life. They are not the most well built to begin with and the chlorine is rough on the bearings and end bells and starting switch if there is one.

Five years is about right and then it would be time for a new pump seal and bearings but not many motor shops are going to service a motor that size and it is only a couple hundred bucks to buy a whole new one.
 
I think that motor amp nameplate value is indicating what the amp draw is when loaded to its max service factor loading. If the running amps on high speed are anywhere close to that, you're most likely pumping too much water. A motor runs hotter than normal when running at its SF amps instead of its native horsepower rating.
 
Apparently the bearings went on the first motor. The pump is fine but the motor is what is the problem. He replaced the seal and the motor.

Being that 240 v is what is available it seems like 208 would be more than 10% that is why I am question how the motor can run on both voltages. Is there some electronics in the motor now that reads the voltage and makes the change?
 
Dennis Alwon said:
Apparently the bearings went on the first motor. The pump is fine but the motor is what is the problem. He replaced the seal and the motor.

Being that 240 v is what is available it seems like 208 would be more than 10% that is why I am question how the motor can run on both voltages. Is there some electronics in the motor now that reads the voltage and makes the change?
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On these slash rated motors 208 is the minimum voltage it will run on. It will not run (long if at all) at 10% below 208.
230 X 90% = 207
230 X 110% = 253
 
Dennis Alwon said:
Apparently the bearings went on the first motor. The pump is fine but the motor is what is the problem. He replaced the seal and the motor.

Being that 240 v is what is available it seems like 208 would be more than 10% that is why I am question how the motor can run on both voltages. Is there some electronics in the motor now that reads the voltage and makes the change?
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If he could have found someone to replace the bearings he likely could have got another five years out of the original motor. It was a mechanical problem that caused the motor to fail, not an electrical one. The pump seal can start to leak a little bit and just the chlorine environment is enough to age the bearings. 208V, 251V, 230V, 240V, 209V, 222V, 233V, wouldn't have mattered.

The motor can run on both voltages because the windings, insulation, fan, etc are configured in such away to make it work, there is no electronics. It's kind of like your car being able to run when it is a quart and half low on oil. The tolerance is built in from the factory.
 
Dennis Alwon said:
Apparently the bearings went on the first motor. The pump is fine but the motor is what is the problem. He replaced the seal and the motor.

Being that 240 v is what is available it seems like 208 would be more than 10% that is why I am question how the motor can run on both voltages. Is there some electronics in the motor now that reads the voltage and makes the change?
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I just checked voltage @ line side of my well VFD. 248 volts and I would guess that is typical for my house.

208-230 volt motor would have an operating range of 188-253 volts then? Plus/minus 10%.

Add: Apparently, looking at the two comments posted just prior to this, there is still arguments as to the actual allowable voltage range of this motor.
 
ActionDave said:
Huh? I'm of the opinion that the voltage is just fine.
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ActionDave said:
Huh? I'm of the opinion that the voltage is just fine.
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FWIW, I agree, its just fine as applied to this motor.

Why do they bother with adding the 208-230 if it means nothing? Better labeling would be as Hv&Lv has the range. 207-253

IDK what areas of this country have voltage consistently below 207. Ours would typically be closer to 212 on a wye.
 
Dennis Alwon said:
Apparently the bearings went on the first motor. The pump is fine but the motor is what is the problem. He replaced the seal and the motor.

Being that 240 v is what is available it seems like 208 would be more than 10% that is why I am question how the motor can run on both voltages. Is there some electronics in the motor now that reads the voltage and makes the change?
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The motor is rated for 208 and 230 volts so the 10% of 230 volts is still OK. The Table in Article 430 states that the 230 volt rating in that table is for 220-240 volts.

Table 430.248 Full-Load Currents in Amperes, Single-Phase Alternating-Current Motors
The following values of full-load currents are for motors running at usual speeds and motors with normal torque characteristics. The voltages listed are rated motor voltages. The currents listed shall be permitted for system voltage ranges of 110 to 120 and 220 to 240 volts.
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ptonsparky said:
Why do they bother with adding the 208-230 if it means nothing? Better labeling would be as Hv&Lv has the range. 207-253
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Because in T430.248 a motor operating at 208 volts has a different current value than one listed for 230 volts.
 
ptonsparky said:
208-230 volt motor would have an operating range of 188-253 volts then? Plus/minus 10%.

Add: Apparently, looking at the two comments posted just prior to this, there is still arguments as to the actual allowable voltage range of this motor.
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No argument. I think the voltage is fine in Dennis’s case.
208-230 means the motor will operate at 207V. NOT 10% below 208.
If it’s a 208 service they will then need a 200V motor.
 
Motors rated for 115/208-230 volt and 208-230/460 volt
These in most cases will operate satisfactorily at 208 volts, but the torque will be 20% - 25% lower. Operating below 208 volts may require a 208 volt (or 200 volt) motor or the use of the next higher horsepower, standard voltage motor.



 
I guess the only motors I remember were something like120/240. This was 208-230 so with the range I wasn't sure if the 10% was still acceptable. Again if they can make a motor that could be wired from 208-230v then why not just go to 240V? That entire 230v is odd to me.

Remember I did a thread on an elevator that was rated 230v. We installed 240v to it and the elevator company made us install a buck boost. Hard to believe 240V was an issue
 
I do appreciate all the comments. The nameplate is new to me with many factors especially the amps having sf and then the amps- never saw that either. I have been out of the field mostly for the past 11 years
 
The 208-230v range rating is based on what is expected at the motor terminals, not to designate the supply voltage.

Such a motor will run satisfactorily on any voltage within 200 to 250 volts, with the current inverse to the voltage.

A motor rated for 208-230/460v is actually rated for 208-230/416-460, but we don't normally see 416v systems.
 
LarryFine said:
The 208-230v range rating is based on what is expected at the motor terminals, not to designate the supply voltage.

Such a motor will run satisfactorily on any voltage within 200 to 250 volts, with the current inverse to the voltage.
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That motor won’t last with 200V
If it starts at all. Probably will start unloaded, but not with a load.
 
Hv&Lv said:
That motor won’t last with 200V
If it starts at all. Probably will start unloaded, but not with a load.
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I was approximating, but there is no one minimum voltage threshold that applies to all 208v motors.

I'm pretty sure that any motor rated for 208v will start and run on a solid 200v, but it will run hotter.
 
LarryFine said:
I was approximating, but there is no one minimum voltage threshold that applies to all 208v motors.

I'm pretty sure that any motor rated for 208v will start and run on a solid 200v, but it will run hotter.
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On that same note wont a motor rated 230v not last as long at 243V
 
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