opens to isolate the inverter. The backfeed protection contactor is normally-
closed, ready to support the static switch, unless the bypass input source
becomes unavailable.
If the UPS transfers to the bypass mode from the double conversion (normal)
mode due to any reason other than operator intervention, the UPS automatically
attempts to transfer back to the double conversion (normal) mode (up to 3 times
within a 10-minute period). The 4
th
transfer locks the critical load to the bypass
source and requires operator intervention to transfer.
3.2.4
Stored energy mode
The UPS automatically transfers to the stored energy mode if a utility power
outage occurs, or if the utility power does not conform to specified parameters.
In the stored energy mode, the battery provides emergency DC power that the
inverter converts to AC power.
Figure
shows the path of electrical power through the UPS system when
operating in the stored energy mode.
Eaton 93E Generation 2 UPS 100-200 kVA
(380/400/415V)
User's and installation guide
©
Eaton Corporation plc 2019. All rights reserved.
Revision: 002
Document ID: P-164000848
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