Contax SW 2524, Owner'S Manual, Page: 299 / 322

Correcting Multiwire Branch Circuit Wiring
976-0043-01-01 F–5
Correcting Multiwire Branch Circuit Wiring
Acceptable options Correcting multiwire branch circuit wiring is not easy. Two options which
will correct multi wiring branch circuit wiring are:
•
Rewire existing multiwire branch circuits to conventional “home run”
wiring. This requires a qualified electrician (knowledgeable about
multiwire branch circuit wiring) and is expensive. There may be
multiple multiwire branch circuits located throughout the structure,
requiring complete rewiring.
• Add a second inverter in a “series stacked” arrangement. This is an
expensive solution, but would restore the original 240 Vac split-phase
configuration. This solution may actually be less expensive than
having an electrician re-wire the multiwire branch circuits. It also
provides increased power backup protection and can power 240 Vac
loads.
Recommended
option Add a T240 Autotransformer to the output of the inverter to restore the
split-phase configuration. This is the least expensive and easiest method
to correct for multiwire branch circuit wiring. Refer to
Figure F-5 . Using
this method, half of the current is supplied to one leg of the circuit and
half to the other in a split-phase arrangement (180° out-of-phase). This
will restore the original functionality and safety to the multiwire branch
circuit.
WARNING: Fire Hazard
Until one of the solutions above is implemented, a stand-alone
120 Vac inverter (or generator) must not be installed where
multiwire branch circuits exist.