If the input power fails to return or is not within the acceptance windows required for normal operation, the battery will continue discharging until a DC voltage level is reached where the inverter output can no longer support the connected loads. When this occurs, the unit will issue another set of audible and visual alarms indicating SHUTDOWN IMMINENT. Unless the rectifier has a valid input soon, the output will only be supported for 2 minutes before the output of the system shuts down. If the bypass source is available, the system will transfer to Bypass instead of shuting down.

If at any time during the battery discharge the input power becomes available again, contactors K1 and K5 are closed and the rectifier will begin to supply DC current to the boost converter and inverter. The battery contactor K2 is opened while the battery charger is turned back on to begin recharging the battery. At this point, the unit returns to normal operation. Depending on the amount of load on the system and the duration of the battery discharge, battery current limit alarms may be seen for a short time due to the current required to recharge the battery.

The systems total operating time on battery will depend on many factors. Some factors that affect battery support times are battery type and capacity, number of parallel strings, environmental temperatures, age of the battery, and fluctuations in load demand during the discharge. The greater the load, the less support time the battery will have. Decrease the load, and the battery support time will generally increase.

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Powerware 9330 (10 kVA--40 kVA) Installation and Operation

 

164201300 REV. G 061502

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Powerware 9330 operation manual 164201300 REV. G