ASEA AC55LC-3, Operation Manual

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AC55LC-3, AC63LC-3, and AC75LC-3 Operations Manual....
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5.3 ELECTRICAL INSTALLATION, cont.
5.3.5 Seamless Transfer Connections
If the Seamless Transfer Option was ordered with the system, connections must be made between the
generator/switchgear and converter. These connections are used by the converter to successfully
manage Seamless Transfer operation and are comprised of control, signal, and feedback functions.
These connections are only required in the Master cabinet of a multi-cabinet installation. Use of 14-
18AWG wire is recommended for signal and control wiring.
A variety of Seamless Transfer Option types exist. These include two generator, three and four
generator, Hybrid (switchgear cooperative), and Clean Bus types. Installation requirements for such
options vary in accordance with switchgear design and hence are beyond the scope of this Operations
Manual.
Contact the factory for complete and specific system wiring drawings. These can be supplied
in either printed or electronic format .
The Seamless Transfer Option uses momentary control signals to operate switchgear contactors or
circuit breakers that mange generator connection to the ship’s distribution bus. The control pulse
width for these momentary control signals is 0.6 seconds for both the open and close commands.
The contacts used for generator control are rated for a maximum of 8A @250VAC or 5A @24VDC.
The generator contactor or circuit breaker must be equipped with an auxiliary switch contact set—
closed when the main contacts are closed.
Generator voltage sense wires are used by the converter to match its output voltage, frequency, and
phase angle to the generator’s and should be fused at the generator/switchgear.