Paul351W
Member
We have a lot of equipment in our facility that have multiple motors powered from one disconnect or power plug. The motors are 480 volt, and we like to monitor the 480 power to the motors to make sure that the power is enabled when we try to start the motor with the PLC. We install a 480v to 120v transformer and run a relay to send a signal to the PLC. We do this because the motor starter will still pull in if no 480 power is present.
For single motor setups this works great, as we put the transformer after the disconnect and fuses. On multiple motor setups however, we only monitor the power after the main fuses in the cabinet.
Has anyone used/seen/heard of a motor contactor that does not pull in if the line side 480 power is not present?
For single motor setups this works great, as we put the transformer after the disconnect and fuses. On multiple motor setups however, we only monitor the power after the main fuses in the cabinet.
Has anyone used/seen/heard of a motor contactor that does not pull in if the line side 480 power is not present?