163-6. Operating Mode DescriptionOperating mode Description LCD displayOnline mode When the input voltage is within acceptablerange, UPS will provide pure and stable AC powerto output. The UPS will also charge the battery atonline mode.ECO mode Energy saving mode:When the input voltage is within voltageregulation range, UPS will bypass voltage tooutput for energy saving. The UPS will alsocharge the battery at ECO mode.AECO mode(AdvancedEfficiencyCorrectiveOptimizer)When the input voltage is within setting range (±3%Vo max), UPS will bypass voltage to outputfor energy saving. PFC and INVERTER are off atthis mode.FrequencyConverter modeWhen input frequency is within 40 Hz to 70 Hz,the UPS can be set at a constant outputfrequency, 50 Hz or 60 Hz. The UPS will stillcharge battery under this mode.Battery mode When the input voltage is beyond the acceptablerange or power failure, the UPS will backuppower from battery and alarm is sounding every5 seconds.Bypass mode When input voltage is within acceptable rangebut UPS is overload, UPS will enter bypass modeor bypass mode can be set by front panel. Alarmis sounding every 10 seconds.Standby mode UPS is powered off and no output supply power,but still can charge batteries.Fault mode When a fault has occurred, the ERROR icon andthe fault code will be displayed.3-7. Faults Reference CodeFault event Fault code Icon Fault event Fault code IconBus start fail 01 x Inverter output short 14Bus over 02 x Battery voltage too high 27Bus under 03 x Battery voltage too low 28Inverter soft start fail 11 x Over temperature 41 xInverter voltage high 12 x Over load 43Inverter voltage Low 13 x Charger failure 45 x