5.1C Section J Attachment J.01C_DRAFT Maintenance Bypass Configuration And Wiring Diagram (MBP)_08.29.25_C.doc

This is a technical attachment containing the wiring diagram and operational procedures for a Manual Maintenance Bypass (MBP) system designed for Uninterruptible Power System (UPS) installations. The document provides detailed configuration specifications for wall-mounted or free-standing cabinet implementations of the Manual Maintenance Bypass Switch (MMBPS), which enables technicians to safely transition UPS loads during maintenance operations.

The MBP sequence of operation follows a make-before-break protocol that requires placing the UPS unit in Static Bypass mode and using Kirk Keys to systematically control three switches in sequence: Switch No. 1 (closure), Switch No. 2 (opening), and Switch No. 3 (optional load bank testing). The wiring diagram illustrates the interconnections between the UPS three-phase output, essential panel input, maintenance bypass breaker, static bypass breaker, rectifier input breaker, and connections to critical load panels and load banks. The system includes an interlock mechanism with a solenoid-controlled Kirk Key release that coordinates UPS output voltage phasing with the essential panel. Normally Open (N.O.) and Normally Closed (N.C.) switch configurations are specified, along with optional Kirk Key solenoid power connections to ensure safe operational sequencing during maintenance activities.