mjm yachts 40z Downeast, Owner'S Manual

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CHAPTER 6 ELECTRICAL SYSTEM
- 28 - 34z
ll Auto START START HOUSE GENSET
Parallel
DC Breaker Panel This custom MJM panel
includes digital readouts for voltage and amperage
drain on top.
The three round knobs are dimmers for main
saloon and pilothouse overhead lights. If it
appears as though a set of lights are not going on
when the breaker switch is turned on, check to see
that the dimmer switches haven’t been turned all
the way off.
The breaker switches for all the 12v DC equipment
on the boat are clearly labeled and some spares
are available for later installations.
AC Breaker Panels The main AC disconnect
breakers are located at the top of AC Panel #1 and
AC Panel #2. They must be ON for shore-power to
supply the boat’s AC power.
AC Shore 1 (left half) includes breakers for those
items which can be handled by the Mastervolt
Inverter. To use the inverter, (1) the house battery
selector switch must be ON and (2) the inverter
breaker on the AC panel must be ON. Refer to the
inverter/charger manual for more information.
When the Shore 1 shore-power cable is attached
and the Shore 1 select breaker is ON, Shore 1 will
supply AC power to AC Panel #1 (forward side of
panel). With the inverter ON, the shore-power will
override it and the inverter will automatically go
into stand-by mode.
AC Panel Shore 2 (right) is designed for those
items having too much load for the batteries and
inverter, thus requiring either shorepower or the
generator to supply AC power. The high amperage
water heater and air-conditioning systems are best
supplied with a shorepower cord to inlet #2 which
bypasses the inverter and goes right to AC Panel
#2.
The AC Transfer switch allows either Shore 1 or
generator to power the AC Panel #2 circuits.
If this function is utilized, be
aware that using too many AC appliances at once
will cause a shorepower breaker to blow.
Battery Switches are located under the electrical
panel. To use DC components, the HOUSE
battery bank switch must be ON, the top main DC
disconnect breaker on the panel must be ON, and
the component’s respective breaker must be ON.
To start the engines or use the windlass, the
engine START battery switches must remain ON