220v motor question

Old 11-27-02, 04:50 PM
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220v motor question

I am installing a ventilation system that includes a fan,a motor controlled damper and a thermostat in our greenhouse. This equiptment all came as part of the building package. The motor is factory wired with a 240v nema type 6-30 plug. On the 1/2hp. motor tag showing the wiring details I see this:

L2----Grounded Line
(230V Circuit)
I do not understand the "grounded line" reference for L2.
My experience with 220v motors always involved two current carrying wires and a ground wire.
Can someone explain?
Many Thanks.
Old 11-27-02, 07:33 PM
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I don't get it either

A L6-30 plug means it's a 240 volt plug rated for 30 amps (2 hots and a ground wire)

I can't see a 1/2 horsepower motor being supplied with such a large capcity plug since it will only be drawing approx. 3.5 amps
Old 11-27-02, 07:44 PM
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ScrapIron, the motor you have, which appears to be single phase 240 volt, pulls 4.9 amps at full load current according to NEC 2002 table 430-148. Remember, that the inrush current to start the motor is much higher.Now I will share some generalities I have seen in the feild that may or may not apply to your case. Some motors, and almost all multi-tap transformers for lites have one lead dedicated to the different possible voltages which can be applied to the load (ie. a 120 lead, a 220 lead, a 277 lead, a 480 lead.) Some of these voltages require 2 hots-no neutrals, other require 1 hot 1 neutral. Regardless of type, one hot always goes to the appropriate voltage. The other hot, or neutral, goes to the other lead. The other lead is usually more aptly called "common". Your best bet, before a motor is ruined, is to check the install manual or call the manuf. before starting it up.

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