Bypass Mode; Figure 2-12: Path Of Current Through The Ups In Bypass Mode - Eaton 93PR Installation And Operation Manual

If at any time during the battery discharge the input power becomes available again, K1 and K5
close and the UPS returns to normal operation. The UPS will also start to recharge batteries to
restore the capacity.
2.2.3.

Bypass Mode

The UPS automatically switches to Bypass Mode if it detects an overload, load fault, or internal
failure. The bypass source supplies the commercial AC power to the load directly. The UPS can
also be commanded to transfer to bypass manually through the display. The UPS status indicated
on the display is "On Bypass". Figure 2-12 shows the path of electrical power through the UPS
system when operating in Bypass Mode.
NOTE
The critical load is not protected while the UPS is in Bypass Mode.

Figure 2-12: Path of current through the UPS in Bypass Mode

In Bypass Mode, the output of the system is provided with three-phase AC power directly from
the system input. While in this mode, the output of the system is not protected from voltage or
frequency fluctuations or power outages from the source. Some power line filtering and transient
protection is provided to the load but no active power conditioning or battery support is available
to the output of the system in the Bypass Mode of operation.
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