SMARTZONE UPS USER MANUAL
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manually configured into the UPS at setup time. The selected mode will become the
Default state of the UPS until the working mode is manually changed.
Normal Mode
Normal mode (on-line double conversion) is the default working mode of these UPS
units. When the UPS is set for Normal mode, it provides a stable pure sinusoidal AC
power output and charges or maintains the charge on the battery. In Normal mode, the
input and output relays are closed and the bypass relay is open. The rectifier/charger
derives power from the AC Input and supplies DC power to the inverter while
simultaneously charging or maintaining the charge on the battery. The inverter inverts
the DC power to AC power and supplies it to the load with a stable pure sinusoidal AC
voltage and current waveform.
When the UPS is operating in Normal mode, if the input power is lost or has any other
anomalies that are outside of the set ranges:
•
The batteries will stop charging (input relay will open)
•
The bypass relay will remain opened
•
The output relay will remain closed
•
The battery will start providing the DC power to the DC to AC inverter, continuing
to provide uninterrupted AC power to the load.
The UPS is now in the Battery state and will indicate an alarm. The UPS will continue to
provide power to the load for a limited time (runtime of the battery backup system
connected to the UPS for the percentage of load connected).
If an internal or an external output event occurs while operating in Normal mode:
•
The input relay may open (depending on the internal event)
•
the output relay will open
•
The bypass relay will close (assuming the input is not outside of the input bypass
range), continuing to provide minimally conditioned AC power to the load.
The UPS is now in the Bypass state and will indicate an alarm. Refer to
State Transitions Based on External Events
Note:
This unit does have short-circuit protection but only when power is being provided to the
load through the inverter. If the unit is in ECO mode or in the bypass state when a short-circuit
occurs on the output of the UPS, the UPS unit may be damaged.
