Georator T3UPS-13-20K, Instruction Manual

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Usually, the most frequent failures of the UPS occur at the inverter. Therefore, we
have added redundant protection circuitry to protect the inverter. A strong snubber is
added to suppress the spikes and noise, oversized, high quality components are used
throughout, semi-conductor fuses are provided, and ventilation is maximized. The
result of this design is a more rugged, reliable and high efficient inverter. At the same
time, the inverter can sustain overload and high peak current drawn by the load.
Additionally, a longer MTBF is achieved.
1.5. Static Switch
TO TO F
ILTE
R
LO
A
D
RESERVE
F
ILTE
R
LO
A
D
INVERTER
RESERVE
INVERTER
RESERVE MODE INVERTER MODE
The static switch is composed of two pairs of SCRs, connected back-to-back. The
switch can transfer the load from reserve to inverter or from inverter to reserve without
losing power at the output. Therefore, it is a very important portion of a UPS.
Detection circuitry is added to the control circuit to achieve zero dead time transfer.
Extra detection logic is employed to control when the static switch should transfer. For
example, when output is short circuited, under normal mode operation, the UPS detects
the short circuit and stops the inverter. The static switch will not transfer power to the
reserve circuit, which might damage the reserve breaker. In case of an overload, the
UPS will stop the inverter after a period the inverter can endure, and then transfer the
load to the reserve circuit, since the overload capability of the static switch is higher
than the inverter.
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