Purpose of 110V 3 phase?

[electricnova]

Hi,

I have taken over a design engineering job for industry.

The design is using a 400V/110V transformer. Usually, the 110V is single phase. However, in this case it is giving 110V 3 phase 32A.

The 110v 3 phase is for use with 4P 110V socket to run a pump.

Being in the UK, I am used to seeing 110V single phase for this application.

Can someone explain why the 3phase option will have been chosen instead?

Any diagrams will be welcomed.

Thank you

 

[snowhead]

Is the pump something specialised that's only available 3ph 110v?
Or is it in a Special location where the customer has specc'd 110v 3ph?

 

[electricnova]

Is the pump something specialised that's only available 3ph 110v?
Or is it in a Special location where the customer has specc'd 110v 3ph?

Hi, this information is not currently available - awaiting a customer reply. The pump is just a vacuum pump which we normally use single phase for.

I wondered if there were unknown reasons for use of 3 phase instead?

 

[littlespark]

110V such as power tools on building sites are 110V split-phase...Not single phase
ie, there is only 55V to earth, but 110 between the two.

 

[James]

is it 110v between phases or 110v from phase to N?

a lot of equipment from Japan runs on (don't hold me to the numbers here) about 200v phase to phase, that gives around 115v phase to N.
not unusual in machine building circles but i don't see a reason for using it to supply a pump unless there is not an alternative available for 400v

 

[electricnova]

110V such as power tools on building sites are 110V split-phase...Not single phase
ie, there is only 55V to earth, but 110 between the two.

Thanks. On all manufacturers data and our equipment schedules it is referred to as single phase.


Split phase and single phase (3 wire) I believe are the same.

55v to earth is the usual configuration with centre tapped to earth

However you can have the neutral to earth to have the full 110v to earth instead (this is the configuration in my original post)

 

[James]

Split phase is not the same as single phase.
split gives you 2 phases 180degrees apart.

single phase obviously has no phase difference angle.
3 phase has 3 x phase voltages 120degrees apart.

your original post is about 110v 3 phase
however you have just mentioned that you are talking about 110v from phase to earth is this 3 phase? If so then it would be about 200v phase to phase.

a drawing or spec sheet would be really useful at this point.

 

[electricnova]

Split phase is not the same as single phase.
split gives you 2 phases 180degrees apart.

single phase obviously has no phase difference angle.
3 phase has 3 x phase voltages 120degrees apart.

your original post is about 110v 3 phase
however you have just mentioned that you are talking about 110v from phase to earth is this 3 phase? If so then it would be about 200v phase to phase.

a drawing or spec sheet would be really useful at this point.

Sorry, I made an incorrect statement above.

I am looking to understand 3ph 110v.

However, this thread has made me question my understanding of 110v not 3ph (not sure what to call it at this point).

Why is it that manufacturers refer to 110v as single phase? I have attached examples

 

[James]

Three-Phase Power Explainer Video

Take a close look at three-phase power and receive an explanation on how it works.

www.raritan.com

the voltage makes no difference to how many phases there are.

 

[loz2754]

That motor is 3hp not 3ph. Just to state the obvious...