4. Connect the T1, T2, and T3 terminals on the starter to the motor.
5. Disconnect one of the wir e s to the shunt trip contact on the starter. This wire is
disconnected to prev e nt the shorted SCR detect ion from operating the disc o nnect device
while this test is being pe rformed.
6. Close the disconnec t breaker. Check the voltag e fro m the starter line termin al to load
terminal on each phase. The measured voltage sho uld be approximately 0. 58 t imes the
system line-to-line voltage.
If the voltage on any pow er pol e is significantly les s , one or both SCRs in the power pole
may be shorted. See Figu re 48.
7. If a shorted SCR is detected, check for possible shorted connections, system grounds, or
any other condition tha t might be causing the shor t. Rep lacement of SCRs or power pol es
without determinin g the cause of the failure may r es u lt in repeated failure of th e SCRs.
8. When the starte r is running, mea sure the voltage f rom the line sid e to the load side of each
starter power pole. The voltage should be approx i mately 1 to 1.5 vac.
When measuring voltage from line side to load side, observe proper electrical
safety procedures si nc e the power poles have vo lt a ge ap pli ed . This voltage could
be as high as 600 v. Personal injury could result.
DANGER !DANGER