Rewinding from three phase to single phase

[Pucp]

Hi, I have to test a submersible pump (1.6 - 2 Kw and 1.1Kw two pump models)that uses as a standard a 2HP 2 poles three phase electric motor 60 Hz (with all the factors is enough to the power required by the pump) . But now we want to assembly the same 2HP 2 poles 60 Hz but rewinded to single phase (I have calculated that will give 1.3 Kw maximum assuming that losses 30% of its power...is this true), so I will test one model only (1.1 Kw). First clarify me how can this rewinding affect the electrical parameters (cos©, power and others), Second if I want to test it also in 50 Hz what problems can arise or how can this also affect the electrical parameters (for 50 Hz I will need less power due to the affinity laws). Also we have normally 3 power cables and 1 ground cable. Now I suppose that we would have 3 power cables (two for the principal winding and one for the secondary or auxiliar winding) 1 earth, but I also want to use 2 for a Klixon and 1 for a Thermocuple in order to register temperature so I will need 7 cables. Can anyone advice me in this tipe of tests. Thank you in advance

 

[SteveKW]

I suggest a close look at your time & rewind costs versus the replacement cost of a new 2 HP single phase motor first.

Here is a link you may want to look at.

http://www.franklinelect.com/Subm_text/sub.htm

 

[Pucp]

Steve.
The case of the electric motor is done in our foundry, is not the kind of pump that need submersible motor. We request the motor 2HP 2 poles 3 phase electric motor and assembly it into the case of the pump in our factory. This is kind of a R&D test, so want to evaluated not only the cost but the performance of the pump and this motor is what we had right now, if it work be sure that we would ask for a 2HP single phase motor not a rewinded one. Thank you.

 

[jbartos]

Suggestions marked ///\\\: ///This posting could make a motor manufacturer R&D busy for a while to obtain accurate answers for you.\\Pucp (Materials) Oct 29, 2002
Hi, I have to test a submersible pump (1.6 - 2 Kw and 1.1Kw two pump models)that uses as a standard a 2HP 2 poles three phase electric motor 60 Hz (with all the factors is enough to the power required by the pump) . But now we want to assembly the same 2HP 2 poles 60 Hz but rewinded to single phase (I have calculated that will give 1.3 Kw maximum assuming that losses 30% of its power...is this true
///Please, notice that the single phase motor power factor and efficiency very somewhat widely. 30% losses could be about right depending on the motor manufacturer and motor quality or price. Easiest way to get reasonable answer is by comparison those two motors data from some manufacturer catalog that offers these two catagory of motors, e.g. Baldor motors, etc.\\), so I will test one model only (1.1 Kw). First clarify me how can this rewinding affect the electrical parameters (cos©, power and others),
///The single phase power factor will be lower/worse, efficiency will be lower/worse, maintenance and operation cost higher, life-cycle lower, etc.\\\
Second if I want to test it also in 50 Hz what problems can arise or how can this also affect the electrical parameters (for 50 Hz I will need less power due to the affinity laws).
///60HZ motor running on 50Hz supply has to have the terminal voltage lowered.\\ Also we have normally 3 power cables and 1 ground cable. Now I suppose that we would have 3 power cables (two for the principal winding and one for the secondary or auxiliar winding) 1 earth, but I also want to use 2 for a Klixon and 1 for a Thermocuple in order to register temperature so I will need 7 cables. Can anyone advice me in this tipe of tests.
///It just depends what you need to have tested. Normally, the connections are made internally inside the motor or motor terminal box, so that there will be a need for two power supply conductors for the overall motor test and 1 cable for the thermocouple.\\ Thank you in advance