So I'm trying to understand now just how to wire up a 240v 2 speed pump but how they work. From what I read there is a high speed, lower speed and common terminal. In 240 volts does one hot leg go to common and the other hot leg go to high or low speed depending on what you want? Or does the high AND low speed terminal get the other hot leg when you decide you want high speed mode? I'm guessing to control this you would use a SPDT relay coupled with a SPST relay. The SPST relay would decide whether or not the power is delivered and the SPDT relay would choose either the high or low speed terminal.
240v two speed pump wiring
- Thread starter piku
- Start date
Just swapped my single-speed motor for a 2-speed last week. The common terminal gets one leg of the 230v, and the other hot leg is switched between
the high and low speed terminals. All I've got for "control" is a switch on the rear of the motor for high or low speed.
the high and low speed terminals. All I've got for "control" is a switch on the rear of the motor for high or low speed.
Ideally you want to turn power off to both leads when the pump is completely off. To do that you would use a DPST relay to turn the pump on and off and a SPDT to change speed. Everything will still work correctly with only one leg turned off, ie the pump will turn off, but it won't be as safe.