Zeva EVMS V2 User manual

Zero emission
Vehicles AustrAliA
http://www.zeva.com.au
Electric Vehicle
Management System
v2.0
The ultimate multifunctional,
integrated control system for your EV
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.
It combines many common functions and a range of fault detection, providing warnings of
operating errors and automatically responding to serious faults.
Instrumentation including voltage, current, power, battery charge, temperature, and•
insulation integrity.
Analog gauge outputs to re-use OEM fuel gauge, temp gauge and tachometer.•
Battery management including cell voltage and temperature monitoring with auto-•
matic response to under/over-charged batteries, and automatic pack balancing.
Contactor control for management of auxiliary contactors, allowing battery pack•
break-up and isolation for safety when vehicle is not in use.
Optional 2-stage precharger with fault detection for soft-starting motor controllers•
Detection of over 15 different operating errors/warnings.•
A complete EVMS consists of a Core, usually installed in the vehicle’s engine bay,
communicating over industry-standard CAN bus with a Monitor module in the vehicle
cabin, and battery management modules located within your battery boxes.
This manual describes the installation and operation of both the EVMS Core and EVMS
Monitor devices. Please refer to documentation supplied with your BMS modules for
information relating to those devices.
Safety Warning
Electric vehicles are high powered machines 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: 12V nominal (9-18V maximum)•
Traction pack voltage range: 12-320VDC nominal (±1% accuracy)•
Traction pack capacity: 10-1000Ah•
Current measurement: Up to ±1200A (±1% accuracy)•
Dimensions (EVMS Core): 150x100x50mm•
Casing: Fully enclosed die cast, weatherproof to IP65•
Fusing: Internal PTC type, 5A for power outputs, 200mA for logic I/O•
EVMS Core Installation
The EVMS Core should be mounted securely to the vehicle using screws through the four
5mmholesonthecaseanges.TheEVMShas20I/Oscrewterminalconnectionsonthe
barrier blocks on top of the case, plus dual CAN ports on one side. Wire gauge for most
connections should be around 18-20AWG to ensure reasonable mechanical strength. Any
HV wiring should have appropriate insulation rating – beware that most automotive insulated
wire is not rated for the higher voltage of EV traction circuits. The supplied fork crimp lugs
are recommended for the most reliable connections to the screw terminals.
Description of EVMS Core connections
Terminal name I/O Description
+12VDC 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 Sense 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).
5V Out Output Independently fused 5V output, used for powering the
current sensor
Current Sense In Input Return line from the current sensor, a 0-5V analog level
Ground For connecting the ground wire on the current sensor
cable.
Main Ctr Cathode Input Connect to the power terminal on the controller (output
/ cathode) side of your main contactor
HV+ Input Connect to the most positive potential of your battery, or
the input / anode of your main contactor.
HV- Input Connect to the most negative potential of your battery (or
negative terminal of motor controller)
Main Ctr Coil+ Output To the positive wire of your main contactor coil. The
contactor coil negative wire must be connected to
ground/chassis.
Main Ctr Switch Input Attach to one of the wires of your contactor’s auxiliary
switch, if it has one. The other wire of the switch should
be connected to ground/chassis.
Aux Ctr Coil+ Output To the positive wire of your auxiliary/secondary
contactor(s). The coil negative wire must be connected
to ground/chassis.
Aux Ctr Switch Input Attach to one of the wires of your contactor’s auxiliary
switch, if it has one. The other wire of the switch should
be connected to ground/chassis.
Charge Enable Output Connect to the +12 terminal of a relay which can enable
your charger (usually turning the AC supply on, or charge
enable input pins supported by some chargers). The other
side of the relay should be connected to ground/chassis.
Ground A spare ground connection point, often used as a ground
return for temperature sensor wiring.
Temp In Input Input Connect one of the temperature sensor wires to this
pin. The other wire should go to ground/chassis.
Temp Gauge Output To the temperature sensor input connection on your
vehicle’s OEM instrument cluster.
Fuel Gauge Output To the fuel tank sensor input connection on your vehicle’s
OEM instrument cluster.
Tach Gauge Output To the tachometer input connection on your vehicle’s
OEM instrument cluster.

Wiring Diagram
ThediagrambelowshowstypicalwiringforacompleteEVMSinstallation.ItmaylookalittleintimidatingatrstbutshouldbecomeclearasyoustarttowireupyourownEV.Notethatthediagram
does not show an inertia switch (crash sensor), which should be installed between the 12V battery and the EVMS Core’s 12V supply. You will also usually need to 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.

CAN Bus Wiring
The EVMS Core has two CAN bus ports (5-pin aviation plugs) 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 5-pin Molex C-Grid SL series plugs for
CAN bus connections. Wiring is shown in the diagrams below:
Shield
CAN L CAN H
Gnd 12V
Shield
CAN L
CAN H Gnd
12V
CAN pin assignments
as viewed on EVMS Core
CAN pin assignments
as viewed on EVMS Monitor
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.Most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.
The EVMS Monitor is most commonly installed at one end of the CAN bus so only has a
single CAN port, and a built-in internal termination resistor. The monitor may be installed
in the middle of a CAN bus by creating a short Y-branch off the bus to the Monitor’s CAN
plug, and removing the small pin jumper beside the plug to disable the internal termination
resistor.
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 wire for maximum noise immunity. Very short
connections are usually OK with untwisted and/or unshielded cable.
CANbusesdrawasignicantamountofpower(thefullEVMSandBMSwillbeusinginthe
order of a few hundred milliamps) so in order to reduce quiescent drain on the auxiliary
battery, the EVMS Core will power down the CAN bus after 1 minute in Idle state (neither
driving, charging, or in Setup). Setup mode can only be entered from Idle state, so this one
minute window will give plenty of time to enter. The Core will also provide 1 minute of CAN
power after powering up.
If the outputs are disabled due to a BMS error (such as an over-voltage or under-voltage
cell), the CAN bus will remain powered up for 1 hour. This is to allow a window for the BMS
modules to continue pack balancing after the charger has been shut down, before the CAN
busispowereddowntoavoidatteningtheauxiliarybattery.
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: Idle
Voltage
Current
Power
Temp Aux V Charge
- 13.0V 100%
–
–
–
The default display when the vehicle is idle (neither
driving nor charging). Battery state of charge and
auxiliary battery voltage are visible, but other
parameters are only available while driving or
charging.
EVMS: Running
Voltage
Current
Power
Temp Aux V Charge
23˚C 13.5V 90%
148V
42A
6.2kW
The standard display when Precharging, Running or
Charging, showing instantaneous voltage, current,
power, temperature, auxiliary battery voltage and
traction battery State of Charge.
Touching the left or right half of the display will swap
to the previous or next display page respectively.
BMS Summary: 45 cells
Avg voltage Balance
Min voltage Max voltage
M0 C4 M2 C8
3.32V 90%
3.31V 3.33V
BMS summary page, showing the total number of cells
being monitored, the voltage and location of both the
lowest and highest cells, the average voltage per cell,
and a metric for pack balance.
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 Core 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 do a
manual reset of the State of Charge (back to 100%),
enter the Setup mode, or switch the display off.
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:
Pack capacity
Value:
100Ah
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
<
<
<
>
>
>
The page for conguring your battery pack (so the
BMS knows how many cells to monitor) looks like
this.
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 Core
The following table describes the parameters available in the General Settings page.
Name Range Description
Pack capacity 10-1000Ah The rated capacity of your traction battery pack,
in Amp Hours. For lead acids, use the C20 rate
(see also section on Peukert’s Effect).
SoC warning 0-99% The EVMS can raise a warning when the traction
battery’s SoC reaches a predetermined level.
Use 0% to disable.
Full voltage 1-400V The EVMS uses a “full voltage” threshold
combined with charge current dropping to
under 2 amps to detect charge completion, and
automatically reset the SoC to 100%.
Warn current 0-1200A The EVMS will provide a warning if the current
in the traction circuit exceeds this threshold.
Trip current 0-1200A The EVMS will provide a warning and
automatically shut down the traction circuit if
current exceeds this threshold.
Temp warning 0-150C TheEVMSwillprovideawarningifitstemperature
sensor exceeds this threshold. It will not shut the
vehicle down, but it is recommended that you
stop to investivate as soon as possible.
Min aux voltage 10-14V If the vehicle’s 12V supply drops below this
threshold for more than 5 seconds, a warning
will be provided. It may indicate a weak 12V
battery and/or faulty DC/DC converter.
Max leakage 0-100% A warning will be raised if isolation integrity
from traction circuit to chassis drops below this
threshold, indicating compromised insulation
or an unexpected conduction path. See also
section on Leakage / ground fault detection.
Tacho PPR 1-6 The EVMS Core can drive your vehicle’s
OEM tachometer as an ammeter, displaying
hundreds of amps instead of thousands of RPM.
Tachometers typically expect a number of
Pulses Per Revolution, being half the number of
cylinders that the original engine had.

Fuel gauge full 0-100% Because every vehicle’s OEM gauges have
different scaling, these four parameters allow
the EVMS Core to tune it’s outputs to suit your
gauges. When these parameters are selected
for editing, the EVMS will drive the appropriate
gauge for the current parameter, allowing you
to tune the gauge visually. (Note that you may
need the key in the On position to power the
instrumentcluster,butenterSetuprst.)
Fuel gauge empty 0-100%
Temp gauge hot 0-100%
Temp gauge cold 0-100%
Peukert's Exp 1.0 - 1.3 Allows adjustment of Peukert’s Exponent
so the EVMS can compensate for discharge
characteristics of different battery types. See
also section Peukert’s Effect.
Enable precharge YES/NO The EVMS Core’s internal precharge can be
disabled, but make sure your controller does
not require it or contactor damage may result!
Enable aux swch YES/NO If your contactors have auxiliary switches, turn
this setting on for monitoring the switch status.
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 the “Stationary
Applications” section for more information.
Current sensor 300A, 600A,
1200A
Selection of the current sensor size (as shipped
with your EVMS Core)
Display brightness 0-100% Adjusts the brightness of the LCD display’s
backlight.
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
Core’s saved settings (they will automatically be reset to
defaults). Contact us if you see this one.
Overcurrent warning If battery current exceeds the programmed threshold for more
than 1 second, this warning will appear.
Overcurrent shutdown As above, except the EVMS will also automatically shut down
the traction circuit if this threshold is exceeded. Note that for
safety reasons this system cannot replace a real fuse, though it
can usually avoid blowing the real fuse.
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.
Low battery charge The battery’s State of Charge has reached the programmed
warning threshold.
Over-temperature The EVMS Core’s temperature sensor has reported a temperature
above the programmed warning level.

Insulation fault A chassis leakage above the programmed threshold has been
detected. (May indicate an insulation fault, or even water inside
a DC motor.)
Low 12V battery The voltage of the 12V auxiliary battery (power supply for the
EVMS) has dropped below the programmed threshold. May
indicate a weak battery or faulty DC/DC converter.
Precharge failed Displayed if an error is detected during the precharge sequence,
either failing to start (usually a wiring fault) or taking too long to
nish(usuallyanunexpectedload“downstream”fromthemain
contactor). The startup sequence is cancelled automatically.
Contactor seized If using contactors with auxiliary switches and a discrepancy
is detected (contactor closed when it should be open, or vice
versa), this error will be displayed.
BMS - comms error If the EVMS Core 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.
Comms error to Core If the EVMS Monitor hasn’t received data from the Core for
more than 1 second, this error will appear. Most commonly this
is due to a wiring fault on the CAN bus.
Peukert’s Effect
All batteries exhibit a reduction in available capacity depending on how fast they
are discharged, known as Peukert’s Effect. For most lithium batteries in EVs the effect is
negligible,butforleadacidbatteriesitcanbequitesignicant.TheEVMScanautomatically
compensateforPeukert’sEffectfordifferentbatterytypes.ThePeukert’sExponentismodied
in the EVMS Core settings to suit your battery type as follows:
Peukert’s Exponent Chemistry and type Capacity at 1C
1.0 Lithium: LiCo, LiMn, LiFePO4 100% of C20
1.1 Lead acid: AGM 75% of C20
1.2 Lead acid: Gel cell 55% of C20
1.3 Lead acid: Flooded 40% of C20
Lead acid batteries have a capacity rated at C20 – that is, how many amp-hours the battery
cansupplyifdischargedovera20hourperiod.Whenconguringthepackcapacityinthe
EVMS, use the C20 rate. Lithium batteries are typically rated at 1C, but they exhibit minimal
Peukert’s Effect so it is close enough to their C20 rate.
State of Charge drift and synchronisation
The EVMS uses a hall effect sensor for current measurement and, by integrating current over
time, calculating battery state of charge. While offering easy installation, safe isolation and
good linearity, hall effect current sensors can exhibit a small amount of zero-point drift and
inaccuracy at low currents, which can accumulate over time causing the reported SoC to
differ from the actual SoC. To mitigate this, the EVMS includes a system to automatically
resynchronise the SoC at the end of any full charge cycle, via programmable “Full voltage”
setting. Ideally, set this to a volt or two below the peak charge voltage of your charger. This
way at the end of each full charge, the SoC will be synchronised back to 100%.
The SoC can also be manually reset to 100% via the Options menu of the EVMS Monitor.
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.
Use with system voltages above 320VDC nominal
The EVMS Core’s internal voltage measurement and isolation monitoring circuit has an
absolute maximum voltage rating of 400VDC, making it suitable for nominal battery pack
voltages up to about 320VDC. The Core may be used with higher voltages, but the HV+, HV-
and Main Ctr- connections must be omitted. Precharging and isolation monitoring no longer
supported, and system voltage is instead calculated from the sum of all cells connected to
BMS modules.
Leakage / insulation fault detection
The EVMS Core has an internal high resistance connection (200Kohm) between the traction
circuit and the vehicle chassis. By monitoring microamps of current owing across this
resistor, the EVMS Core can detect if the isolation between traction circuit and the vehicle
chassis is compromised, such as from damaged wiring insulation, excessive carbon buildup

in DC motors, or even a human touching a HV terminal.
Thisisquantiedasa0-100%range,where0%representsaverylowresistancepathbetween
the traction circuit and the chassis, and 100% represents no detectable leakage. The default
warning threshold for leakage is 50%, which is usually sensitive enough to detect if a human
touches any of the HV terminals. Ideally, you should see over 90% at all times.
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