SMARTZONE UPS USER MANUAL
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when an internal or an external output event occurs (depending on the event). The UPS
may also be set to the Bypass state by turning OFF the invertor, but the input voltage
and frequency must be within the specified upper and lower limits of the bypass as
specified during the UPS setup. For the 5-20kVA UPS units, turn ON/OFF the inverter
through the Common Menu page. While the UPS is in the Bypass state, the source
power is minimally conditioned. Most variations in frequency and voltage will get passed
on to the load.
If an internal or an external output event occurs while operating in the Bypass state, the
UPS will transition to the Fault state and the output will shut down, AC power to the load
will be lost.
Maintenance Bypass State
Maintenance Bypass state is supported on the 3-Phase UPS units only. Manual
intervention is required to transition into and out of this state. This state also requires a
Maintenance Bypass Switch (MBS) unit, sold as a UPS accessory. The UPS may be
switched into the Maintenance Bypass state, through a sequence of switches on the
MBS unit, to perform periodic maintenance on the UPS. The MBS unit will electrically
disconnect the UPS from the system. In the Maintenance Bypass state, the source
power is provided to the load with no power conditioning. All UPS maintenance should
be performed in off hours by qualified personnel only.
If input power is lost while operating in the Maintenance Bypass state, AC power to the
load will be lost.
Refer to the
Maintenance Bypass Switch (UMB20K)
section in this document.
Fault State
The UPS automatically transitions into the fault state when the UPS is unable to provide
power to the load. The input, output, and bypass relays will all open. If the fault clears,
the UPS should transition back to the Default state (depending on the fault that is
cleared).
Battery Test State (Self-Check State)
The UPS may be manually or automatically put into the Battery Test state (sometimes
referred to as the Self-Check State), but the UPS will automatically transition back to the
Default state when the test is complete. The battery test will automatically run when the
UPS is powered ON and periodically while the unit is operating. The battery test may
also be manually executed at any time. The frequency and duration of the battery test
may have an impact on the battery life. All battery tests are preset for a duration of 10
