Blue Sea Systems 9077 AC Rotary Switch - OFF + 3 Positions 240V AC 65A - Manual (Page 2)

Installation (continued)
 Test the third soucre in a similar manner.
 Set the Selector switch to OFF, turn the shore power breaker
to OFF, and leave the load panel circuit breakers in the OFF
position. Complete the mounting of the switch.
 Set your multimeter to volts.
 Test Shore Power
Connect the shore power cable to the shore power source. Turn
on the shore source to make power available to the boat.
a. Turn the selector switch to SHORE. No Reverse
Polarity lights should be lit, and power available should
be indicated. If any red Reverse Polarity lights are on,
turn off the shore power circuit breaker and disconnect
the shore cord at the shore source. Either the hot and
neutral or hot and ground wires have been reversed.
Starting at the distribution panel, trace the connections
as far back as necessary to locate the error.
b. If there are no indications of reverse polarity, check to
see that power is available. If the electrical distribution
panel has a meter, verify that shore power is available
and at the proper voltage. If there is no meter, turn
on the load circuit breaker for an AC circuit powering
a convenience outlet and use a voltmeter to verify
that power is available from line to neutral at the plug.
Verify that there is no voltage between ground and
neutral.
 Test Generator System
Turn the circuit breaker at the shore source to OFF. Set the
selector switch to OFF. The shore power available lights should
all be off. Start the generator and turn the generator breaker to
ON.
a. If there are power available lights for the generator
output, they should light.
b. There should be no power available indication at the
shore power circuit breaker.
c. Set the selector switch to GENERATOR. Power
should be available at the power distribution panel. If
the electrical distribution panel has a meter, verify that
power is available and at the proper voltage.
d. There should be no power available lights indicating at
the shore circuit breaker.
 Test the third soucre in a similar manner.
The Purpose of the AC Source Selector Switch
Alternating Current (AC) power changes polarity 60 times per second in the
US, Canada and Latin America and 50 times per second in Europe. This is
the frequency of the power and is referred to as Hertz (or the now outdated
term “cycle”). Because of this alternating nature of AC power, two live
sources of AC power, such as shore power and inverter power, or shore
power and a generator, cannot be electrically connected. The AC Source
Selector switch is designed to connect two sources of AC power to a
common circuit while preventing both sources from being connected to the
circuit simultaneously.
Useful Reference Books
• Calder, Nigel (2005). Boatowner’s Mechanical and Electrical Manual
(3d ed). Camden, ME: International Marine / McGraw-Hill.
• Wing, Charlie (2006). Boatowner’s Illustrated Electrical Handbook
(2d ed). Camden, ME: International Marine / McGraw-Hill.
Other Innovative Products from Blue Sea Systems
• 360 Panel System
• Battery Management Solutions
• AC and DC circuit protection devices
• WeatherDeck™ waterproof panels
• BusBars, fuses, and fuse blocks
• Analog and digital meters
It is possible to verify most connections using an ohmmeter before
power is applied. These procedures take a little time, but are
recommended, especially if some elements of a previous installation
might not have been clearly or correctly labeled or follow the expected
color codes.
There are many possible sources that may be selected using this
switch, and they may be arranged in any order. The following test
instructions are generally suitable for shore and generator installations.
The third source may be another shore power inlet
or an inverter or other specialized source.
 Test Shore Connection to Switch
Disconnect the shore power cord from the shore power source
and bring the shore plug aboard to a point close the switch panel.
Connect the other end of the shore cord to the boat’s power inlet.
Turn on the shore power circuit breaker between the inlet and the
selector switch. Set the selector switch to OFF.
a. Use an ohmmeter to check for continuity from the shore
ground plug to the green wire at the electrical panel.
b. Check for continuity from the power cord plug neutral
pin to the white wire for this source at the selector
switch.
c. Check for continuity from the power cord plug L1 pin to
the L1 connection for this source.
d. Check for continuity from the power cord plug L2 pin
then L2 connection for this source. Generally the
assignment of L1 and L2 is arbitrary and they may be
interchanged.
e. Check that there is a high resistance (> 1000 Ohms)
between the neutral conductor and the grounding
conductor. There may be indicator lamps in this circuit,
but nothing more than that with the switch in the off
position.
 Verify Switch Selects Shore Input
With the shore cord still disconnected from the shore and
available onboard, and the generator set still not operating, set
the load circuit breakers to OFF, so there is no load at the output
side of the selector switch.
a. Verify that the there is a high resistance between
the line and neutral of the load side terminals of the
selector switch. Again, there may be indicator lamps
in this circuit but the resistance should be greater than
1000 Ohms if the indicators are LED or small lamps.
b. Set the selector switch to the position corresponding to
this shore inlet. The ohmmeter should still indicate a
high resistance.
c. Short the line 1 pin to the neutral pin of the shore plug
and verify that the line 1 to neutral at the load side of
the selector changes to a low resistance. Short the
line 2 pin to the neutral pin of the shore plug and verifly
that line 2 to neutral connection at the load side of the
selector has changed from high to low resistance.
 Verify the Generator Wiring
Turn the generator circuit breaker to OFF and set the selector
switch to the generator position. All load circuit breakers should
still be off. Leave the shore input circuit breaker in the on
position.
a. Verify that there is a high resistance (>1000 Ohms)
from each line to neutral.
b. Verify that there is a low resistance from the neutral to
ground at the load connections.
c. With the generator still not running, close the generator
circuit breaker at the generator. Verify that there is
now a low resistance from each line to neutral where
the generator windings are now connected across the
circuit.
d. Verify that there is still a high resistance from neutral
to ground and neutral to each line at the shore power
plug.
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