Installation
The BMS16 should be mounted securely using screws through the holes on the case flanges.
Install the BMS16 in a location protected from direct sun and water and close to the cells if
possible to minimise cell wiring lengths (under 1m recommended).
The BMS16 has a pluggable screw terminal block for the (up to) 17 cell connections, with
the most point of the battery pack connected to the terminal near C00, and successive
positive terminals connected to C01-C16. Wire gauge around AWG20-26 is recommended
for sufficient mechanical strength and suitable current rating. We recommend wiring up the
plug and verifying all voltages before connecting to the BMS. The plug requires a significant
amount of force to fully engage; ensure it is plugged all the way in for reliable connections.
If you need to disconnect the cell plug from the BMS, significant force is required for removal
as well. For easier removal, a flat blade screwdriver may be used to lever the positive end of
the plug out first, which should then be loose enough to remove by hand.
Ensure that all wiring is secured so it will not become damaged from vibration or abrasion.
Optionally small fuses (~1A) may be used to protect wiring, best installed close to each cell
terminal. Power is always taken from the most positive input C16. If using the module with
fewer than 16 cells, simply add a short jumper wire from your most positive cell terminal to
C16. An example wiring diagram for 16 cells is shown below:
Relay outputs are floating / isolated, and have a maximum rating of 60V and 1.3A continuous.
Be sure to include a flyback diode (if not built in to the relay/contactor) to suppress inductive
voltage spikes from switching the relay coil. In installations with a single “battery enable”
relay, the LV and HV relays may be wired in series such that either an over-voltage or under-
voltage condition will open the relay to isolate the battery pack.
Once your wiring is complete, use a small screwdriver to press the power button on the
top left of the case, and the status LED should come on. A green light indicates all cells are
within correct voltage range, and both relay outputs will be closed circuit. A steady red light
indicates one or more cells are over-voltage, and the HV Relay outputs will be open circuit.
A blinking red light indicates one or more cells are under-voltage, and the LV Relay outputs
will be open circuit. Green/red flashing indicates an over-temperature shutdown.
Current Shunt
The BMS16 may be supplied with either a 100A, 200A or 500A rated shunt. These are
continuous current ratings, but the BMS can measure up to twice the rated current
intermittently. Note that the current shunt may get very hot with sustained current above
its continuous rating. The shunt is connected via two wires to the shunt terminals on the
BMS16. For best performance, twisted pair wire is recommended. The sample wire from the
anode / positive side of the shunt (closest to the +ve of the battery) should be connected to
the terminal nearest the edge of the BMS. When used with a monitor, the current displayed
is discharge amps – i.e charge amps will be negative values. If your polarity seems to be
reversed, simply swap the two shunt wires into the BMS.
Temperature Sensing
The BMS16 is supplied with a 10Kohm NTC thermistor for temperature sensing. It is
connected to the two Temp screw terminals at the rear of the case, and is non-polarised.
It is recommended that the temperature sensor be installed somewhere near the middle of
the pack, since this is typically the warmest location (wires on the sensor may be extended
as long as necessary). The default temperature limit of 80˚C suits most lithium battery types.
CAN Bus Wiring
There are four screw terminals for connecting the BMS16 to a CAN bus, and a Molex C-Grid
SL plug on the optional BMS Monitor, with the following pin identifications:
CAN pin assignments on BMS16 housing
Shield
CAN L
CAN H
Gnd
12V
CAN pin assignments on Monitor housing
