StacksVerified U.S. regulatory reference

49 CFR §193.2613

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
Each auxiliary power source must be tested monthly to check its operational capability and tested annually for capacity. The capacity test must take into account the power needed to start up and simultaneously operate equipment that would have to be served by that power source in an emergency.