TSC 80 TRANSFER SWITCH CONTROLLER
PM063 Rev 7 09/02/27
Thomson Technology
14
3.
OPERATING INSTRUCTIONS
To operate the TSC 80 controller and associated transfer switch using the front faceplate
pushbuttons, refer to the following detailed operating instruction sub-section descriptions.
3.1.
AUTOMATIC SEQUENCE OF OPERATION
3.1.1. NORMAL OPERATION
Under normal operating conditions, the transfer switch operates automatically during a
failure and restoration of utility power and does not require operator intervention.
When utility supply voltage drops below a preset nominal value (70 - 95% of rated
adjustable) on any phase, an engine start delay circuit will be initiated and the transfer
to utility supply signal will be removed (i.e. contact opening). Following expiry of the
engine start delay period (0 - 60 sec. adjustable) an engine start signal (contact
closure) will be given.
Once the engine starts, the transfer switch controller will monitor the generators
voltage and frequency levels. Once the generator voltage and frequency rises above
preset values (70 - 95% nominal adjustable) the Engine Warm-up timer will be
initiated. Once the Engine Warm-up timer expires (0-60 sec. Adjustable), the transfer
to generator supply signal (contact closure) will be given to the transfer switch
mechanism. The load will then transfer from the utility supply to the generator supply
via motor driven mechanism.
The generator will continue to supply the load until the utility supply has returned and
the retransfer sequence is completed as follows: When the utility supply voltage is
restored to above the present values (70 - 95% of rated adjustable) on all phases, a
transfer return delay circuit will be initiated. Following expiry of the utility transfer
return timer (0 - 30 min. adjustable), the transfer to generator supply signal will be
removed (contact opening), then the transfer to utility supply signal (contact closure)
will be given to the transfer switch mechanism. The load will then be transferred from
the generator supply back to the utility supply. During the utility re-transfer sequence a
neutral position delay circuit will cause the transfer mechanism to pause in the “neutral
position (i.e. with both transfer power switching devices open) for the duration of the
Summary of Contents for TSC 80
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