Filter
Top Products
Table 13 — Cutler-Hammer Solid-State Starter Troubleshooting Guide
Problem Probable Cause Area of Correction
CB trips (electrically
operated disconnecting
means opens) as it is
closed.
Motor is not connected. Connect motor to starter.
Incorrect phase sequence to the starter, 3-
phase power not connected, or terminal
loose.
Switch two incoming power leads. The 50
and 51 corresponding motor leads must
also be switched to maintain the same
motor rotation.
Shorted SCR. Perform shorted SCR check.
Shunt trip contact between terminals closes
due to shorted SCR.
Perform shorted SCR check.
Shunt trip latching relay not reset (if used). Reset STR relay by pushing RESET but-
ton on relay.
CB trips while motor is
running.
Microprocessor detected non-standard
operation.
Check wiring to logic module or replace
logic module.
CB trips when STOP is
pressed.
Voltage drop across SCR (looks like
shorted SCR).
Check SCR.
Starter does not pick up
and maintain.
Line voltage is not applied. Check incoming lines for proper voltage.
Overload is not reset. Reset overload.
120 v control voltage is not present. Check control transformer fuse. Check
control circuits.
Heatsink overtemperature switches are
open.
Check for continuity through overtemper-
ature switches. Check that all fans are
rotating freely. Check for excessive motor
current draw.
Starter maintains but
motor does not acceler-
ate or does not attain
full speed (stalls).
Current limit is too low. Increase current limit setting clockwise.
Set ramp time to minimum (counterclock-
wise).
Insufficient Torque. Improper current feedback. Check current feedback resistor for
proper calibration.
High breakaway torque required. Load is not suitable for reduced voltage
starting.
Motor accelerates too
slowly.
Current limit is too low. Increase current limit setting clockwise.
Ramp time is too long. Decrease ramp time setting counterclock-
wise.
Broken current feedback resistor. Check by recalibrating CFR.