Carrier PC211 specifications

reduced at start-up, the starting torque is reduced as well. The object is to reduce the starting voltage to just the voltage necessary to develop the torque required to get the motor moving. The voltage and current are then ramped up in a desired period of time. The voltage is reduced through the use of silicon controlled rectifiers (SCR). Once full voltage is reached, a bypass contactor is energized to bypass the SCRs.

WARNING ! WARNING

When voltage is supplied to the solid-state circuitry, the heat sinks within the starter are at line voltage. Do not touch the heat sinks while voltage is present or serious injury will result.

There are a number of LEDs (light-emitting diodes) that are useful in troubleshooting and

starter checkout on Benshaw, Inc. solid-state starters. These are used to indicate:

•voltage to the SCRs

•SCR control voltage

•power indication

•proper phasing for rotation

•start circuit energized

•overtemperature

•ground fault