European motor wiring
European motor wiring
(OP)
We have three new pumps with single phase 230V Italian (Lowara) motors. The only three terminals for wiring are "L", "N" and ground. I guess the "L" is meant for a 230V single line (as it is in Italy)and the "N" for neutral. Is there any way to wire this to our two wire 230V supply? Our vendor told us to run 115V lines to "L" and "N", and neutral to ground. That doesn't sound right. Can anyone offer advice? Thanks!





RE: European motor wiring
Gunnar Englund
www.gke.org
RE: European motor wiring
RE: European motor wiring
If so, your motor will also rerate to 276 volts. Even at 276 volts, davidbeach's post is true. At 230 volts the chances of overloading are even worse.
If, however, the motor has been designed for 60hz. for export, it should work fine.
If it is a 50hz. motor, (it will say on the nameplate)check the current when you put it in service. If the current is less then the rated current, you have no problem. If the current is more than the rated current try to borrow a transformer or auto transformer and boost the voltage up to 276V more or less.
If the pump is overloading, there is still something you can do.
On a centrifugal pump you may reduce the load by throttling the pump discharge.
respectfully
RE: European motor wiring
Gunnar Englund
www.gke.org
RE: European motor wiring
This line also had some Italian direct current motors which use square frames instead of the round frames that Baldor uses.
Your Italian single phase motor probably is rated 50 Hertz but under U.S. rules you need to rename L and N as L1 and L2 if connecting to 120/240 single phase or to a 240 delta system. If your 240 volts is derived from 277 volts from a buck-boost transformer then leave the labeling as is and connect N to the neutral wire that comes out of the buck-boost transformer.
Germany also makes 60 cycle motors for export to North America, Australia, and some South American countries. At a factory where I worked I had to convert a German machine from 240 volts corner grounded to 277Y480 volt operation. The 2 lubrcation pumps were 9-lead 240x480 U.S. dual voltage and the two 10 HP motors were 240 delta by 416 wye 6 lead. I had to install 3 1 KVA 240 volt by 32 volt buck boost transformers to get 240Y416 volts.
Mike Cole, mc5w at earthlink dot net
RE: European motor wiring
The pumps are hooked up and running, but the motors run hot; the thermal overloads trip occasionally (and automatically reset after a few minutes). They are rated at 230V, 60hz, single phase. Our voltage averages 245. Is that a factor in running hot? Or perhaps the motors are undersized for their job?
RE: European motor wiring
What type of pumps are these?
If they are centrifugal pumps I would (and have many times) restrict the discharge of the pump until the current drops a few percent.
You may want to borrow a 240V/12V transformer and use either an autotransformer connection or a buck connection to drop the voltage 5%. If the motor current drops and the motor runs cooler, it is an indication that the 245V is too high.
respectfully
ps. Thanks for the comments Gunnar. It means a lot coming from someone of your knowlege and experience. I am also honored to be included with someone with the expertise of davidbeach.
wr
RE: European motor wiring