eTower Installation Manual Revision 0
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2.2.12
Circuit Breaker
Each eTower module is fitted with a 125A DC rated circuit breaker to provide overcurrent
and short circuit protection as well to switch the battery module onto and off the DC bus.
Once the modules are all connected and it is safe to apply power to the DC bus, switch on all
the module circuit breakers in quick succession starting with the top module set at address
01. The SoC and On and Run LED’s should illuminate. The breaker serves as the means to
disconnect the battery from the DC bus. After switching off the breaker and thus
disconnecting the module from an external voltage source such as the inverter, the BMS will
shut itself down after 24 hours of inactivity. There is no way to force off the BMS and nor
would it ever be necessary.
2.2.13
Inverter RS485 Interface RJ45 Plug
This plug is used to connect the battery external control communications to RS485
compatible inverters (see Freedom Won Inverter Interfacing Guide). The eTower is
packaged with a cable suitable for use with the Voltronic range of inverters such as the
Axpert. For assistance with other inverter types running on RS485 communications please
contact Freedom Won.
Although not needed when using the supplied cable, for information, the pin configuration
of this interface plug is as follows:
RS485 Inverter Interface Plug Pin Configuration
RJ45 Plug Pin Numbers
Corresponding Signal Wires
1, 8
RS485-B
2, 7
RS485-A
3, 4, 5, 6
No Connection
2.2.14
Inverter CAN Bus Interface RJ45 Plug
This interface is used to connect to CAN Bus compatible inverters and system controllers.
There are two cable types with differing pin configurations included in each eTower
package, one to suit Victron, and the other to suit what Freedom Won describes as Type 1
CAN Bus inverters. See the Freedom Won Inverter Interfacing Guide for complete details.
Although not needed when using the supplied cables, for information, the pin configuration
of this interface plug is as follows:
CAN Inverter Interface Plug Pin Configuration
RJ45 Plug Pin Numbers
Corresponding Signal Wires
1, 2, 3, 6, 7
No Connection
4
CANH
5
CANL
