2.6 RETURNING
FROM
MANUAL
BYPASS TO NORMAL OPERATION
(4-18kVA)
Step 1:
Turn QS5 (battery switch) on.
Step 2:
Turn QS1 (input switch) on. (Note: This switch controls both the utility and
the bypass paths in dual input machines.)
Step 3:
Verify that inverter is OFF. As a precaution press and hold the inverter
stop button for at least 2 seconds.
Step 4:
Turn QS4 (output switch) on. Wait for approximately 5 seconds.
Step 5:
Turn QS3 (bypass switch) off.
Step 6:
Press the inverter start button for 5 seconds.
Step 7:
The green LED on the front panel shall illuminate.
2.7 SYSTEM
DESCRIPTION
This system is an Uninterruptible Power System (UPS) intended to power critical loads
without interruption in the event of utility power failure. This system is connected between
the utility line and the critical load or other selected emergency branch circuits. The
selected loads will continue to receive sinusoidal AC power during the utility power failure.
A block diagram of this system is found in
Figure Y
.
The Synthesis™ can operate in either “Line Interactive” or “Double Conversion” mode,
depending on the condition of the utility input. In Line Interactive mode, the load is
powered through the reserve static switch. In the event of a power event, the load is
transferred to the inverter for a time period determined by the duration and severity of the
power disturbance, and then transfers back to the reserve line. In Double Conversion
mode, The AC input power is rectified to DC to power the inverter and charger. The
inverter converts this to AC to power the load through the inverter static switch. If utility
power fails the rectifier stops operating and the battery supplies power to the inverter
which continues powering the load with no interruption.
If an overload or fault condition occurs in the inverter, the inverter static switch opens and
the reserve static switch closes. This allows the load to continue operation but with no
back up in case of utility failure.
If utility power is restored before the rated discharge time of the battery the rectifier will
start supplying DC power to the inverter and charging the battery. If utility power is not
restored before rated discharge time the inverter will stop supplying power to the load.
When utility power is later restored the system will resume operation automatically.
NOTE: If utility power is not restored for an extended period (36 hours or more) the
battery switch QS5 must be opened to protect the battery from severe discharge. In this
case the system must be re-started manually.
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