UPS for 480 Vac Grid, User Guide, doc. rel. 4.0
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standby state. Meanwhile, the rectifier continues to charge the dc converter that charges the
battery during ECO Mode.
When the UPS in ECO Mode detects an irregularity in the bypass input, the UPS transfers the load
to the Inverter and feeds the load conditioned power.
The advantage of operating a UPS in ECO Mode is that, in effect, the UPS operates as a stand-by
UPS. The UPS uses the rectifier and dc converter modules to charge the batteries while keeping
the inverters on standby. In ECO Mode the UPS can provide a cost savings of at least 2 or
3 percent of power consumption.
4.5.
External Manual Bypass mode
By using external manual bypass mode you force the system to transfer and remain in bypass
mode. This insures a smooth transfer of the active load and ability to safely isolate the UPS.
For additional information about configuring your site for external bypass mode,
refer to the instructions in the Installation Guide.
There may be occasions when your UPS service engineer needs to perform maintenance on the
UPS but does not want to risk the possibility of disturbing or unintentionally disconnecting the
load. The Maintenance Bypass function routes the load power completely around the UPS,
allowing the engineer to isolate the UPS from all power sources, eliminating the technician's
exposure to live power.
Depending on your site setup, without Maintenance Bypass mode, safe
maintenance procedures may require an interruption of the power to the load.
Maintenance Bypass breakers must be fitted with a normally open and normally
closed aux contact. The normally open contact needs to be wired to the forced
bypass terminal and the normally closed contact needs to be wired to the system
controller manual bypass contact to ensure the system is on bypass during transfer
to Maintenance Bypass.
