Optional Connections - Victron energy MPPT 150/85 Anleitung

Solar array Solar array
MPP-voltage MPP-current
[V] [A]
72 67
90 54
108 45
Note 1: highlighted cable cross sections: minimum cross section due to thermal limit.
Note 2: please consult local regulations regarding maximum allowed current carrying capacity of cables.
Table 2: PV cable cross section and power loss

3.4 Optional connections

3.4.1 Voltage Sense
For compensating possible cable losses during charging, two sense wires can be connected
to measure voltage directly on the battery. Use wire with a cross-section of 0,75mm² and
insert a 0,1 Amp fuse close to the battery.
During battery charging, the charger will compensate the voltage drop over the DC cables
up to a maximum of 1 Volt (i.e. 1V over the positive connection and 1V over the negative
connection). If the voltage drop threatens to become larger than 1V, the charging current is
limited in such a way that the voltage drop remains limited to 1V.
The warning triangle on the LCD will blink if the voltage drop reaches 1 Volt
3.4.2 Temperature Sensor (see figure 1)
The temperature sensor supplied with the product may be used for temperature-
compensated charging. The sensor is isolated and must be mounted on the battery minus
pole.
3.4.3 CAN bus interface
The charger is equipped with two CAN bus RJ45 sockets.
The CAN bus on this charger is not galvanically isolated. The CAN bus is
referenced to the minus battery connection.
The CAN bus interface will be referenced to ground if the minus pole of the battery is
grounded.
In case of a positive grounded system, a CAN isolation module will be needed to reference
the CAN bus interface to ground.
To prevent ground-loops, the charge controller has an internal 33 Ohm resistor between
CAN-GND and the battery minus output of the charge controller.
The end of a CAN cable should have a bus terminator. This is achieved by inserting a bus
terminator in one of the two RJ45 connectors and the CAN cable in the other. In case of a
node (two CAN cables, one in each RJ45 connector), no termination is needed.
8
48V system (solar array up to 4850W)
Power loss Length 2x5 meter
in PV cables
α (%)
mm
1 25
1 16
0,75 16
Length 2x10 meter
2 2
AWG mm
3 35
5 25
5 25
Length 2x20
meter
2
AWG mm AWG
Not
2
recommended
3 35 2
3 35 2