B737-700
Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Critical
Flight Crew Diverted; General Maintenance Action
Aircraft
During the initial phase of cruise; approximately 1 hour into flight the 'standby power off' light illuminated. In addition the cabin crew notified us that the cabin was operating on emergency power with no PA or standard lighting. The QRH was consulted and followed; by placing the standby power switch to 'Batt;' completing the checklist but not extinguishing the light. We then noticed a popped circuit breaker on the p-5 standby power unit panel behind the First Officer; above the cabinet in the back wall. We advised company via ACARS. After consulting with Maintenance and Dispatch we diverted to an enroute airport for maintenance. Upon completion of maintenance we were re dispatched to our destination and continued without issue.
The flight crew of a B737-700 diverted to an enroute airport for maintenance attention following the loss of standby electrical power.