Sea Recovery SRC Aqua Matic 450-1 Owner's Manual page 158

Aqua Matic Modular 450-1800
7 Step Down Transformer used in 3 phase systems only
The Step Down Transformer is not required for single
phase systems. It is only required for three phase
systems. It accepts the high voltage operating power at
its primary and steps the voltage down to 115 VAC out of
the transformer's secondary for primary input power to
the 12 VDC Power Supply.
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