Xantrex Technology Link 2000 Marine Instruments User Manual


 
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REQUIRED READING
Before wiring the LINK 2000, install the shunt as indicated.
All wiring should be done before installing the fuses.
GENERAL NOTES
1) Wiring to the LINK 2000 should be #16 or #18 AWG. (Larger wire is acceptable, but
not necessary.) Wiring should be per NEC or applicable standards.
2) The Shunt Sense Leads should be a twisted pair. Leads up to 1,000 feet long may be
used if they are not run along with other noise-producing conductors. Offset error should
be less than 0.2 amps.
For the easiest installation you may wish to purchase our four twisted pair cable with
the same color code as the meter. This cable may be run between the meter and the batteries
to supply all needed signals. This cable is available from your dealer or from Xantrex.
Note: You may make your own twisted pair wire by chucking up two wires in an electric
drill motor and twisting them by running the drill motor until there is a twist every inch. A
wrap of tape every 16" will keep the wires together and make them easier to pull through
the raceway.
3) Caution! If your starter draws more than 500 amps see #5 below.
4) Battery current is sensed with a shunt, which is a very precise, small resistance. It is
inserted in series (in line) in the negative wire of the circuit you wish to measure. The current
is measured by sensing the voltage drop across this resistance. The LINK 2000 uses
a 50 mV, 500-amp shunt. When 500 amps flows through the shunt, there is a 50 mV drop
across it. Thus 10 amps equals 1 mV or 1 amp equals 0.1 mV. The display is scaled to read
amps. If you wish to check this you will need a very accurate digital meter (Fluke 87 in
4 1/2 digit mode or better) if the current is below 30 amps (3.0 mV). Above 50 amps most
digital meters can be used for testing.
5) Note for Marine and RV installations: If starter current exceeds 500 amps, the starter
negative must be connected to the battery side of the battery shunt so that starter current
does not flow through it. The problem with this is that if the alternator is of the grounded
case type its current will not be flowing through the shunt. The alternator ground must be
isolated from the engine and run to the load side of the battery shunt to be able to measure
the current going into the battery from the alternator. Isolated negative output alternators
are available and we strongly recommend them. With isolated negative output alternators,
CAUTION!!!!
The output voltage of the shunt is very small. It is critical that all of the
connections for the shunt sense leads have the highest possible integrity. Every
effort must be made to prevent corrosion that might affect the sense leads.