A method of testing a distribution center bus system having one or more of the following features: (a) opening a reserve bus breaker between a reserve bus UPS and a reserve bus, (b) initiating a self-test mode at the reserve bus UPS, (c) routing current through the reserve bus UPS, the reserve bus, a reserve bus static bypass circuit back to the reserve bus UPS, (d) testing the reserve bus to detect heat, determine any significant current loss, or identify other attributes suggesting failure, (e) identifying if a primary bus static transfer switch has tripped over to the reserve bus, and (f) terminating the self-test at the reserve bus UPS if the primary bus static transfer switch has tripped.