Cummins Power Generation Combustion Engine RA112N3

Move the operation selector switch on the generator to Stop (Off)

Disconnect the battery charger from its AC power source

Disconnect the generator starting battery (negative [-] lead first)

Remove AC power to the automatic transfer switch

Remove the transfer switch cabinet door panel

Spread the relay clips apart and remove the relay(s) from the relay base(s)

Install the new relay(s) on the relay base(s), ensuring alignment of screw head and hole

Ensure all sources of AC power are removed before beginning installation

Move the generator operation selector switch to Stop

Disconnect the battery charger from its AC power source

Disconnect the starting battery, negative (-) lead first

RA112N3, RA212N3, RA112S3, and RA212S3 Models

Remove all sources of power from the transfer switch

Remove the transfer switch cabinet door panel

RA112N3, RA212N3, RA112S3, and RA212S3 Transfer Switch Replacement

Install the busbars on the new switch according to the markings. Ensure the long end of the busbar is connected to the breaker.

Use previously removed hardware to install the new switch in the cabinet. Torque M6 nuts to 5.6 Nm (50 in-lb) and 1/2-20 screws to 9 Nm (80 in-lb).

Install the bracket at the load and emergency side of the switch using previously removed hardware. Torque M6 nuts to 5.6 Nm (50 in-lb).

Tighten the 1/4-20 bolts securing the mechanical lugs. Torque bolts to 9 Nm (80 in-lb).

Reinstall the cabinet door panel(s).

RA412N3 and RA412S3 Transfer Switch Replacement

Use previously removed hardware to install the new switch in the cabinet. Torque three M8 bolts to 19 Nm (168 in-lb).

Install two lugs to the emergency side of the switch. Torque four M6 bolts to 14 Nm (124 in-lb).

RA112N3, RA212N3, RA112S3, and RA212S3 Transfer Switch Assembly Removal

Remove the applicable door panel(s)

Remove all control and power wiring from the switch terminals

Mark the busbar of each phase of the Utility/Generator and Load, then remove all of the busbars from the old switch

Remove the switch from the mounting panel

Loosen and remove the switch assembly

Loosen and remove the four screws, nuts, and washers securing the switch panel and switch to the rear wall of the cabinet

Loosen the six 1/4-20 bolts securing the mechanical lugs

Loosen and remove the two screws, nuts, and washers securing the bracket at the load and emergency side (bottom) of the switch

Move the operation selector switch on the generator to Stop (Off)

Disconnect the battery charger from its AC power source

Disconnect the generator starting battery, negative (-) lead first

Remove AC power to the automatic transfer switch

Remove the transfer switch cabinet door panel

Mark and disconnect all wires connected to the limit switches

Install the new limit switches using the manual operation handle