Operation
8.7Replacing a Faulty Power Module or UPS Internal Battery
1.Press the UPS’ Off button twice within four seconds to turn off the UPS. The UPS will transfer to Output Off Mode.
2.Turn Off the input and output breakers on the UPS and the corresponding input and output breakers on the parallel POD.
3.Make sure that the single UPS has shut down.
4.Disconnect the parallel communication cable between the UPS and parallel POD.
5.Remove the front bezel cover, battery cover, and battery bracket from the UPS and disconnect the battery connectors. (Refer to the detailed steps in the Liebert
6.Replace the faulty power module or internal UPS battery.
7.Close the corresponding input breaker on the parallel POD and make sure that the UPS’ input phase is correct.
8.Close the UPS’ input and output breakers.
9.Press the UPS’ On button to turn on the UPS.
10.Make sure that the single UPS is operating normally and that its output voltage is the same as the output voltage of the paralleling system.
NOTE
If the UPS’ output voltage needs to be changed with the configuration program, it must be done immediately.
11.Press the Off button of the single UPS twice within four seconds to turn it off.
12.Open the input and output breakers on the single UPS and the corresponding breakers on the parallel POD.
13.Connect the parallel communication cable between the UPS and parallel POD.
14.Close the input and output breakers on the UPS and the corresponding breakers on the parallel POD. The UPS is now in Output Off Mode.
15.Press the UPS’ On button. The UPS will join the paralleling system.
8.8Overload Condition
If an overload is detected in the paralleling system, each UPS works as a single UPS. When exceeding the overload time, each UPS will transfer its mode. The mode transitions and the corresponding con- ditions are listed below.
1.If the bypass is abnormal, the UPS will transfer to No Output Mode (for Battery mode) or overload fault (for Line mode). Users must use the reset button to release the fault.
2.If the bypass is working normally, the UPS will transfer to No Output Mode without overload fault.
3.If the UPS is the last one in the paralleling system and the bypass is working normally, each UPS will transfer to Bypass Mode. After the entire paralleling system has recovered from the overload, the system will restart automatically and return to Line Mode.
4.If the bypass is abnormal, the UPS will transfer to No Output Mode without overload fault for Battery mode, and the UPS will transfer to overload fault for Line mode. When the utility power returns, the paralleling system that its original mode is Battery mode will restart automatically and return to Line Mode.
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