ROD ASSEM. 9H6236 - Caterpillar

System Bypass Options
Note: Refer to this Operation and Maintenance Manual, "Modes of Operation", for a complete description of all System Modes.Internal bypass procedures are used when the system needs to regulate power to the load, but has no need to protect for a utility outage.The bypass circuit powers the critical bus for one of the following reasons:
Maintenance is required.
The UPS cannot maintain voltage to the load, due to an overload that is sustained, or due to a system malfunction.The bypass circuit provides a path for power directly from an alternate AC source. The control system for the UPS constantly monitors the availability of the bypass system circuits, in order to perform a transfer.The bypass system circuit consists of the following components:
Bypass Switch (Static)
Output Contactor (UPS)
Bypass Contactor (System)Note: The Bypass Switch (Static) is an option.The output contactor isolates the UPS from the load. The bypass contactor (system) works in parallel with the static bypass switch, if equipped. The static bypass switch is a solid-state device that can instantly connect the alternate AC source to the load.Note: The static bypass switch is an option.System Bypass Procedure
Illustration 1 g03377486
Touchscreen panel and manual ups controls
(1) Touchscreen
(2) USB port
(3) Two positions "Keyswitch": Normal - Bypass
(4) EPO button
(5) Horn silence button
(6) Operational State LEDsNote: CAUTION: Continuing with this procedure will disconnect the critical load from the output of the UPS. Refer to System Bypass Procedure in this manual, if that option is not desired.
Turn the SIO key switch to the "Bypass" position.
Confirm that the system is in "Bypass" by observing the system mode status in the System Diagram/Overview Screen. Do not remove facility power from the input. The DC Bus and Flywheel will continue to receive power to levitate the flywheel until the DC Disable switch in the SIO cabinet is switched to "Disabled". If working in the FPU cabinet, transfer the switch to "Disabled".Note: CAUTION: While the flywheel is spinning, the DC Bus and armature leads are energized.
Allow the capacitor banks to purge down for approximately 5 minutes to dissipate any residual energy in the bus and armature leads.