Electric Vehicle Management System V3


Download design files:


Files are provided under the open source MIT License.
A copy is included in the ZIP archive.


Introducing Version 3 of our successful Electric Vehicle Management System (EVMS), performing a wide range of common functions for electric vehicles and stationary battery systems including:

BMS master control: Communicates with BMS modules over CAN bus and takes action if any cells go out of safe voltage or temperature range.
Instrumentation such as battery pack voltage, instantaneous current, battery state of charge
Optional staged precharging: Soft-start your motor controller, including error detection in cases of wiring or controller faults.
Contactor control: Management of auxiliary contactors to allow pack break-up when not driving or charging.
Temperature sensor input: For monitoring your motor temperature
Analog gauge outputs: Use your OEM fuel gauge to display battery SoC, your tachometer to display instantaneous amps, and your temp gauge to display motor temperature
Stationary mode, offering behaviour better suited to stationary and off-grid battery systems.
CAN integration with TC, Elcon, Ovartech and Enphase chargers (any supporting TC's CAN protocol) allowing the EVMS to control charger voltage and current, start/stop the charger based on BMS status, and view charger data on an EVMS Monitor.

The EVMS can also detect and warn of a variety of errors:

Monitors traction circuit isolation integrity to detect insulation faults
Overcurrent warning and shutdown (digital fuse)
BMS warning for cells outside safe voltage and temperature
Monitors auxiliary switches on contactors to detect if seized
Monitor 12V supply/battery with adjustable low voltage warning
Low battery SoC warning
CAN communications errors

New functionality and improvements for version 3 include:

Deep sleep mode, for much lower quiescent power consumption when the system is idle (about 3mA)
One multi-purpose input pin, assignable to a range of functions such as wake from sleep, dual charge rate switch, headlight sense, contactor aux switch
Two multi-purpose output pins, assignable to a range of functions such as temp gauge output, low SoC signal, overtemp/undertemp signal, error buzzer, status light
Cell voltage reporting to 1mV resolution, cell voltages viewable in Idle mode
New balancing algorithm performs balancing throughout charge cycle, instead of only at top of charge
Current sensors and current shunt interfaces now run over CAN bus
3D printed housings on all devices, available in custom colours by request.

The EVMS3 is designed to communicate with other devices over CAN bus. A typical installation will also include an EVMS3 monitor (for viewing operating status, errors, instrumentation and BMS information, and configuring the system), BMS modules (for reporting cell voltages and performing pack balancing), and a CAN current sensor (measuring and reporting battery current, for calculating State of Charge, power, etc). Please click on the links below for further information about these associated devices.

Note: The EVMS3 uses an all new CAN protocol so is not compatible with older devices (such as EVMS Core, EVMS Lite V2, Monitor V2, BMS12 up to V1.7).

Related Products

EVMS Monitor V3   $165.00
View information from the EVMS3, BMS12 modules, ZEVA motor controllers, TC Chargers or BMS16 over CAN bus

12-cell Lithium BMS Module V3   $165.00
Automotive grade, CAN bus-enabled battery management and balancing for up to 12 cells per module.

EVMS3 CAN Current Sensor   $125.00
Measure and report battery current to the EVMS3 and Monitor over CAN bus

Temperature sensor for EVMS3, BMS16 and BMS12   $6.00
100Kohm NTC thermistor for use with our BMS12, BMS16 and EVMS3 devices

Gigavac GV240 Contactor   $215.00
800V 400A+ DC contactor


Power supply: 12V nominal (8-20V max)
HV pack voltage: 12-360V nominal (405V absolute max - please contact us to discuss higher voltage systems)
Pack capacity range: 5-1250Ah
Current measurement range: +/-1200A
Outputs internally fused at 5A max
Dual CAN bus ports
Dimensions: 127x94x34mm
Weight: 150g

Datasheets & Manuals:




Zero Emission Vehicles Australia © 2024 :: Terms and Conditions, Privacy Policy, Payments and Delivery, Warranty and Returns