This read-only integer gives the bypass-line current for one UPS phase, expressed in tenths of an amp. It lets an administrator see how much current the load is drawing directly from the bypass source when the UPS transfers load off the inverter, useful for confirming the bypass circuit isn't near its rated limit. A value of 155 means 15.5 amps are flowing on that phase's bypass feed, information an admin would check right after a forced bypass transfer.