Models 5E, 5F, 5G & 5H Electric Switch Machines: Single ... - Alstom

Theory of Operation2.5.2. Hand Crank Cutout SwitchesThe cutout switch, shown in the open position in Figures 2–12 and 2–13, removes allpower to the switch machine motor. The cutout switch is engaged via the mechanicalinteraction of the hand crank being inserted into the blocking plate. To insert the handcrank, the hole in the blocking plate must align with the hole in the clutch pinion. Whenthe blocking plate moves, the contact plunger will also move opening the control line tothe motor armature.ContactsFigure 2-12. Cutout Switch in Open Position (Models 5F and 5H)WARNINGCUTOUT SWITCH CONTACTS CARRY 110-VDC WHEN POWER ISAPPLIED. USE CAUTION WHEN WORKING AROUND EXPOSEDCONTACTS. FAILURE TO DO SO COULD RESULT IN SERIOUSINJURY OR DEATH.NOTEThe crank cutout switch opens the neutral (return) line in the motor circuit.If external power is connected with the cutout switch open, all motorwindings, the “hot” side of the cutout switch, and the motor control circuitswill be energized to 110 VDC.P1293, Rev. Jun/07 2–14 Alstom Signaling Inc.