If one of the voltages is higher than 2 v, but the voltages of the 3 power poles are approximately equal, the starter is probably still in current limit. If the voltage is higher than 2 v on only 1 or 2 power poles, not all SCRs are firing properly. Make sure the gate lead connections are tight. If all 3 power poles have less than a 2 v drop from line side to load side of each starter power pole when the motor is up to speed, any current unbalance in the motor is caused by the motor or an unbalanced line voltage.

Click here for Figure 47 — Resistance Check

Click here for Figure 48 — SCR and Power Poles

Click here for Figure 49 — Typical Cutler-Hammer® Solid-State Starter (Internal View)

Electronic Protection Relay (EPR)

On Cutler-Hammer solid-state starters, the EPR is designed to provide an alternative to conventional motor protection due to overcurrent. See Figure 50. It performs the following functions:

Test Button — The TEST button provides testing of the EPR’s ability to detect overload, test relay operation, and simulate motor load.

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Carrier PC211 specifications Electronic Protection Relay EPR