Water pump with a stinger

[ptonsparky]

You have a small three phase pump motor. 208.
Service is 240v with Hi leg. (We don't care it has one. Your motor does not care)
What is the total distance to where your pump will be? VD can be your friend in this case. Two hundred feet of 14 cu @ 5.9 Amps will give you approx 223 volts at your motor. Within limits.

To confuse things a bit. Get a VFD that allows single phase input and gives you three out. Set the parameters to match that of the motor. I would use the two legs with 120v to ground because the VFD does care about the Hi Leg.

 

[ptonsparky]

An online supplier lists a general purpose VFD at under $400.

 

[ptonsparky]

or use a couple buck/boost transformers to drop the voltage. IDK if that would be less than the VFD or not. Your skills will make the difference in what is best for you..

Final option, get a 240v motor. Single or three phase.

 

[oldsparky52]

What do the specifications say, what is the nameplate voltage rating?

 

[infinity]

The voltage from the utility is 120/240 with a high leg of 208v. the pump works

That's a common 3 phase, 4 wire Delta service. The 3 phase pump doesn't care about the high leg.

 

[ActionDave]

That's a common 3 phase, 4 wire Delta service. The 3 phase pump doesn't care about the high leg.

It does if it is a 200V rated motor rather than a 230V.

 

[ptonsparky]

nm

 

[LarryFine]

there is a well pump that is 1.5hp 3phase.

We need to know the motor's voltage rating to advise further.

 

[ptonsparky]

We need to know the motor's voltage rating to advise further.

Ahh, yes. I mistook the 208 as the pump voltage. Wrong again.

 

[infinity]

It does if it is a 200V rated motor rather than a 230V.

A 200 volt motor on a 240 volt system would be an issue whether you had a 3-wire Delta or a 4-wire Delta. Am I missing something?

 

[ptonsparky]

A 200 volt motor on a 240 volt system would be an issue whether you had a 3-wire Delta or a 4-wire Delta. Am I missing something?

No, I think most of us are saying the same thing, but not getting all the details in.

 

[LarryFine]

The only things that matters here are the supply line-to-line voltage and the motor's voltage rating.

 

[Jraef]

Emphasis on LINE-TO-LINE voltage. Again, L-N voltages are totally irrelevant to a 3 phase load.

 

[ActionDave]

A 200 volt motor on a 240 volt system would be an issue whether you had a 3-wire Delta or a 4-wire Delta. Am I missing something?

The OP was less than clear about what his voltage was and what the rating of the motor was. We both agree that three wire or four wire system is of no consequence to the motor. I was focusing on the voltage rating.

 

[norcal]

Lot of people get hung up on the 208V high leg, the voltages are still 240V line to line.

 

[Jraef]

Lot of people get hung up on the 208V high leg, the voltages are still 240V line to line.

That's the truth...

 

[curt swartz]

I'm surprised it was a 208 volt well pump. We just went though it for an upcomming project. Well contractor said the the only pumps he can get are 230 volt. The site has 208/120 & 480/277. He said we would need to install BB's to use the 208. Instead I recommended running 480 to the location then using a 480-240 XMFR. Distance is far anyway so the high voltage saves on wire cost.

 

[ptonsparky]

I'm surprised it was a 208 volt well pump. We just went though it for an upcomming project. Well contractor said the the only pumps he can get are 230 volt. The site has 208/120 & 480/277. He said we would need to install BB's to use the 208. Instead I recommended running 480 to the location then using a 480-240 XMFR. Distance is far anyway so the high voltage saves on wire cost.

We have a customer that is 208. Available if you give enough lead time.

 

[Jraef]

The motor design voltage for 208V systems is actually 200V. But most 230V new motors 10HP and under will say "208-230V" now, because it's cheaper for the motor mfrs to make a small design change than to maintain inventory on specific voltages. What they do is to design the motor as 220V +15%, -10% so that it covers the utility standards for 208V - 5% to 240V +5%. For them, it's just a change in the magnetics, for us, it's either buying different motors or using BB transformers.

What I think happens a lot is that equipment OEMs don't know enough to understand this issue and just put down the first number they see. But when you actually look at the specific motor NAMEPLATE, it will say 208-230V.

 

[Dzboyce]

What brand is the pump motor? Some brands are 240 volt only and have a different motor for 208 volt. The Grundfos is dual rated 208/240 volt 3 phase. Franklin and Pentair are not dual rated. Takes a different motor for 208 volt vs 240 volt. Guess which brand i use when I have 208 volt 3 phase?