Technical data

CORRECTIVE MAINTENANCE
CV ELECTRICAL POWER SYSTEM MAINTENANCE MANUAL 2A5A2-ELEC-MM-1-0 16
4.5 Replacing an HPU Boost Transformer
DANGER!
Shock hazard! Verify power to the unit is isolated before performing this
maintenance procedure. This procedure exposes conductors that carry
high voltage sufficient to cause lethal electric shock.
When performing work in the CV power room, be aware of potential
exposure to high voltages sufficient to cause lethal electric shock.
Drawing References
7533008 CV power system wiring diagram
7533009 Power system assembly (2A5A2)
7533010 Power system cable routing
7533011 CV electrical power system schematic (2A5A2)
7533016 Hotel and HPU transformer wiring diagram
7533327 HPU boost transformer general assembly
7533343 HPU boost transformer assembly
Special Tools
None
Spare Parts
7533343 HPU boost transformer assembly
Preconditions
None
Procedure
1. Follow instructions in Section 6.2, General Notes, regarding hazmat
requirements, torque specifications, inspection of mounting hardware, and use of
Nylok® nuts, as applicable.
2. Perform the following steps in accordance with local requirements for SOC and
tag in/out, as applicable.
3. In the CV, at the
POWER DISTRIBUTION UNIT, set POWER BUS #1 (2A5A2-1B-EP01-1)
and
POWER BUS #2 (2A5A2-CB-EP01-2) to OFF.
4. At the
480 V 3Ø DISTRIBUTION PANEL, turn off BUS #1 MAIN DISCONNECT (2A5A2-CB-
EPO8-1) and
BUS #2 MAIN DISCONNECT (2A5A2-CB-EPO8-2) switches.
5. Disconnect wires at the output transformer terminal beam.
6. Disconnect three (3) power wires and two (2) voltage conditioner wires at the
input transformer tap.
7. Disconnect the ground cable.
8. Remove the transformer sensor panel support straps.