Blue Sea Systems 1801 Vessel Systems Monitor VSM 422 - Manual (Page 6)

CONNECTIONS
Connector Function
Header A Communication *
Pin 1 Communication
Pin 2 Communication
Pin 3 Communication
Header B AC
Pin 1 AC Line
Pin 2 AC Neutral
Header C Sensors and Power
Pin 1 DC Voltage Battery 1 (Unit Power) †
Pin 2 DC Voltage Battery 2
Pin 3 ‡ DC Voltage Battery 3, Tank Level 3, or Bilge Function
Pin 4 DC Negative
Pin 5 Battery Temperature (Positive)
Pin 6 Battery Temperature (Negative)
Pin 7 Tank Level 1
Pin 8 Tank Level 2
Pin 9 DC Shunt (Positive)
Pin 10 DC Shunt (Negative)
Pin 11 AC Current Coil (Positive)
Pin 12 AC Current Coil (Negative)
* Communication port is for use with future modules
† Ampere hours are measured for Battery 1 ONLY
‡ Three input options available
7
A
B
1
1 12
3
1 2
C
2
2 3 4 5 6 7 8 9 10 11
Connector Pin Assignment Table
Specifications subject to change. See www.bluesea.com for current information.
SENSORS
DC Current
The shunt must be placed between the negative terminal on Battery 1 and
the main negative bus.
All loads and charge sources should have their
negative terminals on the main negative bus , with the exception of the VSM
422 negative source which must be connected directly to the battery side of
the shunt. Shunt sense wires must be a twisted pair from shunt to VSM 422
for proper calculation of State of Charge (SOC). Twisted pair wire can be
purchased from electrical supply companies, or made by twisting by hand
or with an electric drill motor. The current reading for Battery 1 when it is not
being charged and has a load should be negative. If it is not, reverse the DC
shunt leads. (see page 95)
DC Voltage
Voltage lines to the VSM 422 should be directly connected to the positive
battery terminal with a dedicated wire ahead of any other connections. This
will ensure correct voltage and SOC monitoring. Use an appropriate in-line
fuse (5A suggested) on the positive wire.
AC Current
In most cases the AC Current Transformer should be located on the main
AC feed before any other devices. See http://bluesea.com/viewresource/86
for more information on AC Current Transformer location. The location does
not affect state of charge (SOC) calculations.
The Current Transformer does not indicate polarity. If AC voltage is applied
and current shows greater than zero but the power reading is zero or a
negative value, reverse the AC Current Transformer leads. The leads should
be twisted to reduce the effects of interference.
AC Voltage
The ungrounded AC line should be fused inline with a fast acting fuse of
0.25A to 0.5A to protect against shorts.
Bilge Sensor
Connect “switch on” lead of bilge pump to the VSM 422 unit. This wire
should read +12/24V when running and 0V when off.
8
Specifications subject to change. See www.bluesea.com for current information.