ot well pump voltage

[jontwo13]

We have been trying to find an answer can we run a--- (single phase)230 volt submersible pump on (single phase) 208 volt. Every person I ask says you can't run it on 208 3 phase. That is not what I asked them.

[QSIMDO]

I asked a similar question once and was told it's all the same.

....?

If it's all the same then why not pick one and be done?

Anyway, result is the pump works just fine.

[Arcane]

Short answer is yes, it will run. If the nametag does not specifically state it is a dual voltage motor(208/230 V), chances are it will burn out when you try to actually pump water with it.

[Evan]

Every person I ask says you can't run it on 208 3 phase. That is not what I asked them.

Actually, that is what you asked. Single phase 208 is what you get from line to line on a three phase service. To run properly the motor must be 200 volt rated. If it isn't it will draw excessive current and overheat.

[Wareagle]

Evan is on the mark. Ohm's law states that for a given load (wattage) if the voltage goes down, the amperage goes up, and vise versa. The motor you have (240 volt) would be running with 208 volts at the best case. Factor in the footage that the circuit is, and there will be some voltage drop in addition to using 208V. The fact of the voltage being low would mean the windings would carry more current than it is designed for to perform the work, and would shorten the life of the motor considerably; if not burn it up in short order.

Your options in this case would be to add a transformer to bring your voltage up to the 240V that you need, find a 208V rated motor, or hook it up and see how long it lasts (with the understanding that it may not live very long).

[J Tiers]

Then again, if you don't ask for max gpm at max lift, it may last a long time.

Just idling at 208 won't hurt it at all, it is the extra current under power that kills it by heating.

Cutting current in half reduces heating by 4X, so even a relatively small amount below full power would have significantly less heating and might make up the 10% difference in voltage.

At 70% power, heating is reduced to half. At 90% power, heating is reduced 20%.

[CCWKen]

LOL... When does a water pump idle?

[RobDee]

It idles in a shallow application like a spring as opposed to a deep well. It runs at reduced load when it is designed to run to a specific depth, say 200' and it is only 100' down the well.

[Evan]

Nope. A pump runs at maximum load when the outlet is at minimum pressure. The lower the outlet pressure the higher the volume of water it moves and the heavier the load.

Example: block the intake of your vacuum. The motor speeds up.

[JCHannum]

The power requirements of a pump, whether loaded or unloaded will depend on the design of the pump.

Positive displacement pumps aside, rotary pumps can have several different designs, a turbine pump will behave quite differently than a centrifugal. A centrifugal with an open face impeller will behave differently than one with a closed face. Impellers can be designed to be overloading or non overloading, and can be trimmed to use only a certain amount of power. There are many more variations that will influence the performance of a pump.

Depending on the application and pump design, the motor may or may not hold up. The best source of information would be to contact the manufacturer or supplier. More information about the performance characteristics of the pump are needed to give good advice.

Generally speaking, running a motor that far below the nameplate voltage will result in it's destruction unless load is reduced. If a clamp on ammmeter is available, the load can be evaluated, and if actual amperage is less than the nameplate by a factor approaching or exceeding the difference in voltage, it will possibly survive.