SERVICE CAGE LEFT FROM BOTTOM APPROXIMATELY 100-150 FT FROM BOTTOM, HOIST TRIPPED OUT. ELECTRICIAN ON JOB COULD NOT GET HOIST TO RESET. AFTER TROUBLE SHOOTING FOR 20 MINUTES OR SO, WE CALLED E LEC ENGINEER. HE TOLD US THINGS TO BE CHECKING WHILE HE WAS ON HIS WAY. WE FOUND MOTOR OVERCURRENT RELAY HAD TRIPPED. WE RESET, RAN CAGE BACK TO BOTTOM, LET PERSON OFF & RAN TEST ROUND & BEGA