Vandenberg AFB – XUMU 12-1269B – Replace 12 KV Switchgear at Substation D – Bldg 1847
Vandenberg AFB, CA

Schwab Engineering has provided professional A/E services to replace existing 12KV switchgear at Substation D, Building 1847 utilizing the latest technology to allow the substation to regain its original reputation as a highly reliable power source. The existing 12KV switchgear has two sources with a tie breaker fed underground directly from two 3.75/4.2MVA, 69-12/6.9KV liquid filled power transformers located at the switchyard. The existing switchgear has nine (9) vertical sections consisting of the following:

• 4-Outgoing Feeder Breakers
• 1-Tie Breaker
• 1-Space for Future
• 2-Space for CPT/control
• 1-Space for Differential Relays

Schwab Engineering recommended replacing existing 12KV switchgear with new metal clad switchgear including components which will be designed, manufactured and tested in accordance with the latest applicable standards of NEMA SG-4 and SG-5 but not limited to ANSI/IEEE 37.20.2. The new 12KV switchgear will have the same ampere rating and short circuit MVA rating as the existing.