Zeva EVMS Lite User manual

Zero emission
Vehicles AustrAliA
http://www.zeva.com.au
EVMS Lite v1.0
Introduction
Thank you for purchasing ZEVA’s Electric Vehicle Management System. The EVMS was
developed to address the need for safer, more reliable and better integrated EV conversions.
The Lite module is a simplied version of our EVMS Core, for those who only need basic BMS
functionality. The Lite communicates with battery management modules over CAN bus and
manages your vehicle’s drive and charge circuits according to battery status, automatically
shutting down the vehicle if any cells exceed safe voltage range.
It also features auxiliary contactor control (for managing any mid-pack contactors), remote
LED for viewing status from the cabin and a buzzer output for audible warnings of any
errors. The EVMS Lite can optionally be used with an EVMS Monitor module for viewing
current vehicle status as well as full BMS information such as individual cell voltages and
pack statistics. The Monitor may also be used for reprogramming BMS parameters over the
CAN bus.
This manual describes the installation and operation of the EVMS Lite, with some additional
content describing interaction with the EVMS Monitor.
Safety Warning
Electric vehicles are high powered devices which involve potentially lethal voltages and
currents. Proper precautions and electrical safety procedures should always be observed,
voltages above 110VDC should be considered dangerous, and vehicles should never be
worked on while power contactor(s) are engaged. Please read this manual carefully to
ensure correct installation and operation. If you are unsure of anything, please contact us
before proceeding.
We have endeavoured to make a safe and reliable product which performs as described,
however since ZEVA has no control over the integration of its products into a vehicle, we can
assume no responsibility for the nal safety or functionality of the completed vehicle.
It is up to the end user to determine the suitability of the products for the purpose employed,
and the end user assumes all risks associated. Products should only be installed by suitably
qualied and experienced persons, and should always be used in a safe and lawful
manner.
Specications
Power supply: 13.5V nominal (8-20V maximum)•
Current consumption: 5mA idle, 25mA active•
Contactor outputs rated at up to 5A•
Dual CAN bus ports (5-pin Molex KK)•
Dimensions: 82x56x10mm•
Weight: 20g•
EVMS Lite Installation
The EVMS Lite should be mounted securely in the vehicle using the four 3mm holes on the
board, in a location protected from the weather. The Lite has nine mini quick connect (spade)
terminals across one edge for its main connections, plus dual CAN ports on opposite sides.
Wire gauge for most I/O connections should be around 18-20AWG to ensure reasonable
mechanical strength and current rating.
The following page shows a typical wiring diagram for an EVMS Lite in a vehicle (plus
associated BMS modules and EVMS Monitor).

Wiring Diagram
The diagram below shows typical wiring for a complete EVMS installation. Note that the diagram does not show a main fuse (5A recommended) and inertia switch (crash sensor), which should both be
installed between the 12V battery and the EVMS Lite’s 12V supply. You will also usually need to separately use the key signal to switch a relay for powering auxiliary devices such as brake vacuum pump,
power steering pump, water cooling pump, cabin heater, etc. Make sure all wiring has appropriate current and insulation ratings, and that fuses have appropriate DC voltage and current ratings.
EVMS Lite
12V
GROUND
KEY IN
CHG IN
LED
BUZZER
DRIVE
AUXCTR
CHARGE
CAN Termination
Resistor 120!
BMS12
Battery Box
EVMS: Idle
Z E V A EVMS MONITOR
< SEL >
Fuse
Charger
Main
Contactor
Relay
Auxiliary
Contactor
BMS12
Battery Box
CAN Termination
Resistor 120!
CAN bus
CAN bus
CAN bus
Traction Circuit HV+
Traction Circuit H V-
DC/DC Converter
Motor Controller
B+
From 12V
Battery
Ground
To LED in dash
Charge Door
AC in
Fuse
B-
To
Motor
Door Switch AC socket
DC Out
+
–
To 12V
Battery
HV In
+
–
LV Out
+
–
To buzzer in dash
Precharger
From key

Description of EVMS Lite connections
Terminal name I/O Description
12V Input To 12V battery positive (permanent supply, not key
switched). Approx 9-18V maximum range.
Ground Input To vehicle chassis, or 12V battery negative.
Key in Input To key signal, should be +12V when key is turned on
Charge In Input Connect to your charge detection switch, such as a fuel
door switch or 240V detect relay/circuit. Should pull to
ground when the switch is on (so attach other side of
switch to chassis, near the switch is ne).
LED Output Allows for wiring of a remote LED for viewing status in
cabin. 5mA limited. Connect this pin to LED anode, and
cathode to ground/chassis.
Buzzer Output Connect a 12V piezo buzzer to this output pin for an
audible warning when errors are detected.
Drive Output Supplies 12V to the main contactor, precharge system or
motor controller while the key is on and the BMS reports
no errors.
Aux Ctr Output Supplies 12V to any auxiliary contactors you may have
such as pack break-up contactors, while either driving
or charging.
Charge Output Supplies
CAN Bus Wiring
The EVMS Lite also has two CAN bus ports (5-pin Molex
C-Grid SL) on one side of the case. These are wired
identically, and can be connected in either order in any
location along the CAN bus. (The EVMS Monitor and
BMS12 modules use the same 5-pin plugs and wiring.)
12V
CAN H
CAN L
Gnd
Shield
CAN pin assignments on 5-pin plugs
CAN buses work best when wired as a single daisy chain of devices, with 120ohm termination
resistors at each end to prevent signal reection. For this reason all ZEVA CAN-enabled
devices have dual CAN ports for easy daisy-chaining. The order of devices is unimportant -
usually the shortest path between devices is best.
For the sake of noise immunity, CAN buses typically use twisted pair cable. Since electric
vehicles can involve high electromagnetic interference (EMI) from the traction circuit, we
recommend using shielded twisted pair (STP) wire for maximum noise immunity. Very short
connections are usually OK with untwisted and/or unshielded cable.
EVMS Monitor
The EVMS Monitor is used to remotely interact with other devices on the CAN bus, both
for viewing operating data and to edit settings. The Monitor has various different pages of
information as described below.
EVMS Lite
System Idle
The default display when the vehicle is idle (neither
driving nor charging).
In order to minimise quiescent power consumption
while the vehicle is not in use, the EVMS Lite will
power down the CAN bus after 1 minute in idle state.
You can use this time window to enter Options and
Settings modes.
EVMS Lite: Running
Pack voltage # Cells
Min voltage Max voltage
M0 C4 M2 C8
149.4V 45
3.31V 3.33V
The standard display when the vehicle is runnng or
charging, showing the pack voltage (total of monitored
cells), total number of cells, and the voltage and
location of both the lowest and highest cells.
Along the bottom is a bar graph showing all cells being
monitored. Green bars indicate cells within range. Bars
will change to blue for undervoltage cells, orange for
cells being balanced, and red for overvoltage cells.
BMS Details: Module 1
Cell voltages
3.32V 3.33V 3.32V 3.31V
3.33V 3.31V 3.32V 3.32V
3.31V 3.32V 3.33V 3.32V
3.32V 3.32V 3.33V 3.31V
Temp1: 23˚C Temp2: 25˚C
Prev Next
Detailed information for a single BMS module,
showing voltage of each cell (to 2 decimal places) and
two temperatures if available. Orange bars beneath
the voltages indicate if cell shunts are currently on.
Touch within the Prev and Next buttons to change
which BMS module is being viewed, or anywhere else
in the display to change Monitor pages.

Warning:
Charge ended by BMS
If the EVMS detects an error, this warning page
will be displayed. In most cases, the error can be
acknowledged/reset by pressing Select. For a full list of
errors you might see, refer to section Error Detection.
Reset SoC
Enter Setup
Display Off
Exit Options
You can bring up this options menu by holding your
nger down for 1 second. From here you can enter the
Setup mode, or switch the display off. (Note that Reset
SoC only works with EVMS Core.)
When the display is off, touch and hold anywhere for
1 second to turn it back on. Display will automatically
wake if there is a new warning to display.
Setup mode can only be entered from Idle state, i.e
when the vehicle is not charging or being driven.
Conguring Settings
The EVMS Monitor can be used to congure settings for all devices on the CAN bus.
EVMS: Setup
General Settings
Parameter:
BMS: Undervoltage
Value:
2.50V
Exit Setup
<
<
<
>
>
>
The Setup mode has three rows. The top row
toggles between the General Settings and the Pack
Conguration sections. Tap the arrows either side to
nagivate between these. In the General Settings page,
the second row selects the parameter to be modied,
and the third row modies the parameter itself.
The Exit Setup button will distribute new settings
to all devices on the network then return to normal
operation.
EVMS: Setup
Pack Configuration
Module ID:
0
Num cells:
12
Exit Setup
<
<
<
>
>
>
This is the page for conguring your battery pack, so
the BMS knows how many cells to monitor.
Tap the arrows either side of the Module ID row to
select the module in question, and the arrows either
side of Num cells is used to modify how many cells
that BMS module should expect.
List of settings - EVMS Lite
The following table describes the parameters available in the General Settings page.
Name Range Description
BMS: Min voltage 0 - 5.00V Adjusts the low voltage warning threshold for
each cell in your traction pack.
BMS: Max voltage 0 - 5.00V Adjusts the high voltage warning threshold for
each cell in your traction pack.
BMS: Shunt voltage 3.00 - 5.00V Adjusts the voltage at which shunt balancers
turn on for each cell in the tracion pack.
BMS: Low temp warn 0-100˚C The EVMS can provide a warning if any BMS
modules report a temperature below or above
these respective thresholds.
BMS: Overtemp warn 0-100˚C
Stationary Mode YES/NO Switches the EVMS into Stationary Mode,
for battery backup and off-grid power type
applications. Please refer to “Stationary
Applications” Section for more information.
Display brightness 0-100% Adjusts the brightness of the LCD display’s
backlight.
Display fade delay 0-20sec Changes the length of time the display will
remain lit after a button press, change of state or
warning notication.
Buzzer On YES/NO Selects whether the Monitor should sound the
buzzer for alerts. (Safest to leave this on.)
Use Fahrenheit YES/NO Changes display of temperature units to
Fahrenheit instead of Celcius.
Error Detection
The EVMS monitors a wide range of operating parameters for your electric vehicle and can
notify you if any exceed their safe range or any faults are detected. In most cases, errors
can be acknowledged/reset by pressing the Select button. Critical errors are responded to
automatically (such as by shutting down the traction circuit due to a critically low cell),
while others are at the driver’s discretion to respond to (such as over-temperature warnings).
The following table describes the errors you may encounter.
Error Description

Corrupt Settings Occurs if memory corruption has been detected in the EVMS
Lite’s saved settings (they will automatically be reset to defaults).
Contact us if you see this one.
BMS - low cell A BMS module has reported a cell voltage below the minimum
threshold.
Shutdown by BMS A low cell condition has been present for more than 10 seconds,
so the EVMS has shut down the traction circuit to protect the
batteries.
BMS - high cell A BMS module has reported a cell voltage above the minimum
threshold.
Charge ended by BMS A high cell condition has been present for more than 1
second, so the EVMS has shut down the charger to protect the
batteries.
BMS - overtemp A BMS module has reported a temperature above the
programmed threshold.
BMS - comms error If the EVMS Lite hasn’t received data from a BMS module for a
while (about 1 second), this error will appear and the traction
circuit will be shut down for safety.
Stationary Applications
The EVMS conguration includes a setting for Stationary Mode, intended for use in battery
backup and off-grid power applications. In this mode, the Key input enables both Main
Contactor and Charge Enable outputs concurrently. An undervoltage cell will disable the
Main Contactor output (to remove any loads on the battery) and an overvoltage cell will
disable the Charge Enable output (to disable any charging sources). In both cases the outputs
are re-enabled once the voltage has recovered by 0.4V (i.e there is ±0.2V hysteresis around
the congured thresholds).
In Stationary Mode, the Charge Sense input is no longer used, typically the Aux Ctr output
will not be used, and precharging is not supported.
For LiFePO4, we recommend an undervoltage threshold of 2.8V (which results in 2.6V cutout
and 3.0V re-enabling for any loads on the battery), and an overvoltage threshold of 3.6V (for
3.8V charger cutout and 3.4V re-enabling). These thresholds give about 1% hysteresis on the
battery state of charge to avoid rapid cycling of the charger or outputs.
Tech notes
• CAN bus power: CAN busses use a signicant amount of power when operating. In order
to minimise quiescent power consumption (and avoid attening your vehicle’s 12V battery),
the EVMS Lite powers down the CAN bus after 1 minute if the vehicle is neither driving or
charging. As such, the BMS will no longer be monitoring your cells so it is of paramount
importance that there are no loads on the traction battery when the vehicle is idle, or
batteries could be damaged from over-discharge!
If the outputs are disabled due to a BMS error (such as over-voltage or under-voltage cell),
the CAN bus will remain active for 1 hour. This is to allow a window for the BMS modules to
continue pack balancing even after the charger has been switched off, before the CAN bus
is powered down to avoid attening the auxiliary battery.
Once the CAN bus has powered down, you will be unable to enter Setup mode with a
Monitor device. To remedy this, simply turn the key on and off, or turn the EVMS Lite off and
on again, then enter Setup as normal within 1 minute.
• Precharging your motor controller: Motor controllers have a large input capacitor bank
which must be precharged / soft started, to avoid a large inrush current when your contactor
closes which can damage components. The EVMS Lite includes no controller precharge
system, so you will need to arrange a precharge device for your motor controller if it does not
have one built in. (Check out our Smart Precharger on the ZEVA website for more info.)
Tech support and warranty information
All ZEVA products are covered by a 12 month warranty against manufacturing faults or
failures under normal operating conditions. The warranty does not cover misuse of the
product, including but not limited to: excessive voltage or reversed polarity on terminals,
short circuits on outputs, opening of housings and/or modication of internal electronics,
severe impact damage (e.g due to vehicle crashes), submersion in water.
We have taken great care to design a safe and reliable product, but faults can happen. If
you believe your product has a fault, please contact us via our website to discuss. If it is
determined that a hardware fault is the likely cause, we will provide an RMA number and
return address to proceed with repairs.
If you have any questions not covered by this manual, please contact us via our website:
http://www.zeva.com.au