Fangpusun BMV-700 User manual

BMV-700
BMV-700H
BMV-702

1 QUICK START GUIDE
2 NORMAL OPERATING MODE
3 FEATURES AND FUNCTIONALITY
4 FULL SETUP DETAILS
5 MORE ABOUT PEUKERT’S FORMULA AND MIDPOINT MONITORING
6 LITHIUM IRON PHOSPHATE BATTERIES (LiFePO4)
7 DISPLAY
8 TECHNICAL DATA
1.1 Battery capacity
1.2 Auxiliary input (BMV-702 only)
1.3 Important combined button functions
2.1 Read-out overview
2.2 Synchronizing the BMV
2.3 Common problems
3.1 Features of the three BMV models
3.2 Why should I monitor my battery?
3.3 How does the BMV work?
3.3.1 About battery capacity and the rate of discharge
3.3.2 About charge efficiency (CEF)
3.4 Several battery state-of-charge display options
3.5 History data
3.6 Use of alternative shunts
3.7 Automatic detection of nominal system voltage
3.8 Alarm, buzzer and relay
3.9 Interface options
3.9.1 PC Software
3.9.2 Large display and remote monitoring
3.9.3 Custom integration (programming required)
3.10 Additional functionality of the BMV-702
3.10.1 Auxiliary battery monitoring
3.10.2 Midpoint voltage monitoring
3.10.3 Battery temperature monitoring
4.1 Using the menus
4.2 Function overview
4.2.1 Battery settings
4.2.2 Relay settings
4.2.3 Alarm-Buzzer settings
4.2.4 Display settings
4.2.5 Miscellaneous
4.3 History data
Safety Precautions
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Working in the vicinity of a lead acid battery is dangerous. Batteries
can generate explosive gases during operation. Never smoke or allow
a spark or flame in the vicinity of a battery. Provide sufficient
ventilation around the battery.
Wear eye and clothing protection. Avoid touching eyes while working
near batteries. Wash your hands when done.
If battery acid contacts skin or clothing, wash them immediately with
soap and water. If acid enters an eye, immediately flood the eye with
running cold water for at least 15 minutes and get medical attention
immediately.
Be careful when using metal tools in the vicinity of batteries.
Dropping a metal tool onto a battery might cause a short circuit and
possibly an explosion.
Remove personal metal items such as rings, bracelets, necklaces,
and watches when working with a battery. A battery can produce a
short circuit current high enough to melt objects such as rings,
causing severe burns.
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1 QUICK START GUIDE
Setup wizard:
This quick start guide assumes that the BMV-702 is being installed for the first
time, or that factory settings have been restored.
The factory settings are suitable for the average lead acid battery:flooded,
GEL or AGM.
The BMV will automatically detect the nominal voltage of the battery system
immediately after completion of the setup wizard (for details and limitations of
automatic nominal voltage detection, see section 3.8).Therefore the only
settings which need to be made are the battery capacity (BMV-700 and BMV-
700H), and the functionality of the auxiliary input (BMV-702).
Please install the BMV in accordance with the quick installation guide.
After inserting the fuse in the positive supply cable to the main battery, the
BMV will automatically start the setup wizard.
The setup wizard below must be completed before other settings can be
made.
Remarks:
a) In case of Li-ion batteries, several settings may have to be changed.
Please refer to section 6. The setup wizard below must be completed before
other settings can be made.
b) When using a shunt other than the one supplied with the BMV, please refer
to section 3.6. The setup wizard below must be completed before other
settings can be made.
1.1 Battery capacity
a) After inserting the fuse the display will show the scrolling text
If this text is not shown, press SETUP and SELECT simultaneously during
3 seconds to restore factory settings or go to section 4 for full setup details
(setting 64, Lock setup, must be OFF to restore factory settings, see
section 4.2.5).
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b) Press any button to stop scrolling and the factory default value Ah will
appear in edit mode: the first digit will blink.
Enter the desired value with the + and – buttons.
c) Press SELECT to set the next digit in the same manner.
Repeat this procedure until the required battery capacity is displayed.
The capacity is automatically stored in non-volatile memory when the last digit
has been set by pressing SELECT. This is indicated with a short beep. If a
correction has to be made, press SELECT again and repeat the procedure.
d) BMV-700 and 700H: press SETUP or + or – to end the setup wizard and
switch to normal operating mode.
BMV-702: press SETUP or + or – to proceed to auxiliary input setting.
1.2 Auxiliary input (BMV-702 only)
a)The display will show scrolling.
b)Press SELECT to stop scrolling and the LCD will show:
Use the + or – key to select the required function of the auxiliary input:
for monitoring the starter battery voltage.
for monitoring the mid-point voltage of a battery bank.
for using the optional temperature sensor
Press SELECT to confirm. Confirmation is indicated with a short beep.
c)Press SETUP or + or – to end the setup wizard and switch to normal
operating mode.
The BMV is now ready for use.
When powered up for the first time, the BMV will display 100% state of charge.
When in normal mode the backlight of the BMV switches off after no key has
been pressed for 60 seconds. Press any key to restore backlight.

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The cable with integrated temperature sensor has to be purchased
separately (part no: ASS000100000). This temperature sensor is not
interchangeable with other Fangpusun temperature sensors, as used
with Multis/Quattros or battery chargers.
1.3 Important combined button functions
(see also section 4.1: using the menus)
a) Restore factory settings
Press and hold SETUP and SELECT simultaneously for 3 seconds
b) Manual synchronization.
Press and hold the up and down buttons simultaneously for 3 seconds
c) Silence audible alarm
An alarm is acknowledged when any button is pressed. However, the alarm
icon is displayed as long as the alarm condition remains.
1.4 Real-time data displayed on a smartphone
With the VE.Direct Bluetooth Smart dongle real time data and alarms can be
displayed on Apple and Android smartphones, tablets and other devices
2 NORMAL OPERATING MODE
2.1 Read-out overview
In normal operating mode the BMV displays an overview of important
parameters.
The + and – selection buttons give access to various read-outs:
Battery voltage
Auxiliary battery voltage
Current
BMV-702 only, when the auxiliary input is set
to START.
The actual current flowing out of the battery
(negative sign) or into the battery (positive
sign).
Power
The power drawn from the battery (negative
sign) or flowing into the battery (positive sign).

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7
Consumed Amp-hours
The amount of Ah consumed from the battery
Example:
If a current of 12A is drawn from a fully charged battery for a period of 3
hours, this readout will show -36.0Ah.
(-12 x 3 = -36)
A fully charged battery will be indicated by a
value of 100.0%. A fully discharged battery
will be indicated by a value of 0.0%.
Time-to-go
An estimation of how long the battery can
support the present load until it needs
recharging.
The time-to-go displayed is the time to reach the discharge floor.
See 4.2.2, setting number 16.
Battery temperature
BMV-702 only, when the auxiliary input is set to
TEMP
The value can be displayed in degrees Celsius or degrees Fahrenheit. See
section 4.2.5
State-of-charge
Battery bank top section voltage.
BMV-702 only, when the auxiliary input set to MID.
Compare with the bottom section voltage to check battery balancing.
For more about battery midpoint monitoring, see section 5.2.
Battery bank bottom section voltage
BMV-702 only, when the auxiliary input is set to
MID.
Compare with the top section voltage to check battery balancing.
Battery bank mid-point deviation
BMV-702 only, when the auxiliary input is set to
MID.
Deviation in percent of the measured mid-point voltage.
Battery bank mid-point deviation voltage
BMV-702 only, when the auxiliary input is set to
MID.
Deviation in Volts of the mid-point voltage.
2.2 Synchronizing the BMV
For a reliable readout, the state of charge as displayed by the battery monitor
has to be synchronized regularly with the true state of charge of the battery. This
is accomplished by fully charging the battery.
In case of a 12V battery, the BMV resets to ‘fully charged’ when the following
‘charged parameters’ are met: the voltage exceeds 13.2V and
simultaneously the (tail-) charge current is less than 4.0% of the total battery
capacity (e.g. 8A for a 200Ah battery) during 4 minutes.
The BMV can also be synchronized (i.e. set to ‘battery fully charged’) manually
if required. This can be achieved in normal operating mode by holding the + and
– buttons simultaneously for 3 seconds, or in setup mode by using the SYNC
option (see section 4.2.1, setting number 10).
If the BMV does not synchronize automatically, the charged voltage, tail
current, and/or charged time may need adjustment.
When the voltage supply to the BMV has been interrupted, the battery
monitor must be resynchronized before it can operate correctly.

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2.3 Common problems
No signs of life on the display
Probably the BMV is not properly wired. The UTP cable should be properly
inserted at both ends, the shunt must be connected to the minus pole of the
battery, and the positive supply cable should be connected to the plus pole of
the battery with the fuse inserted.
The temperature sensor (when used) must be connected to the positive pole
of the battery bank (one of the two wires of the sensor doubles as the power
supply wire).
Charge and discharge current are inverted
Charge current should be shown as a positive value.
For example: +1.45 A.
Discharge current should be shown as a negative value.
For example: -1.45 A.
If charge and discharge current are inverted, the power cables on the shunt
must swapped: see the quick installation guide.
The BMV does not synchronize automatically
One possibility is that the battery never reaches the fully charged state.
The other possibility is that the charged voltage setting should be lowered
and/or the tail current setting should be increased. See section 4.2.1.
The BMV synchronizes too early
In solar systems or other applications with fluctuating charge currents, the
‘charged’ voltage should be set only slightly below the absorption charge
voltage (for example: 14,1V in case of 14,4V absorption voltage). This will
prevent the BMV from switching prematurely to 100% state of
charge. See section 4.2.1.
Sync and battery icon are blinking
This means the battery is not synchronized. Charge the batteries and the BMV
should sync automatically. If that doesn't work, review the sync settings. Or, if
you know the battery is fully charged but don't want to wait until the BMV
synchronizes: press and hold the up and down button simultaneously, until you
hear a beep. See section 4.2.1.
3 FEATURES AND FUNCTIONALITY
3.1 Features of the three BMV models
The BMV is available in 3 models, each of which addresses a different set of
requirements:
1 Comprehensive monitoring of a single battery
2 Basic monitoring of an auxiliary battery
3 Battery temperature monitoring
4 Monitoring of the mid-point voltage of a battery bank
5 Use of alternate shunts
6 Automatic detection of nominal system voltage
7 Suitable for high voltage systems
8 Several interface options
BMV-
700
BMV-
700H
BMV-
702
Remark 1:
Features 2, 3 and 4 are mutually exclusive.
Remark 2:
The cable with integrated temperature sensor has to be purchased separately
(part no: ASS000100000).This temperature sensor is not interchangeable
with other Fangpusun temperature sensors, as used with Multis or battery
chargers.
3.2 Why should I monitor my battery?
Batteries are used in a wide variety of applications, mostly to store energy for
later use. But how much energy is stored in the battery? No one can tell by just
looking at it.

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The service life of batteries depends on many factors. Battery life may be
shortened by under-charging, over-charging, excessively deep discharges,
excessive charge or discharge current, and high ambient temperature. By
monitoring the battery with an advanced battery monitor, important feedback
is given to the user so that remedial measures can be taken when necessary.
Doing this, which extends battery life, the BMV will quickly pay for itself.
3.3 How does the BMV work?
The main function of the BMV is to follow and indicate the state-of-charge
of a battery, in particular to prevent unexpected total discharge.
The BMV continuously measures the current flow in and out of the battery.
Integration of this current over time (which, if the current is a fixed amount of
Amps, boils down to multiplying current and time) gives the net amount of Ah
added or removed.
For example: a discharge current of 10A during 2 hours will take 10 x 2 = 20Ah
from the battery.
To complicate matters, the effective capacity of a battery depends on the rate
of discharge and, to a lesser extent, on temperature.
And to make things even more complicated: when charging a battery more Ah
has to be ‘pumped’ into the battery than can be retrieved during the next
discharge. In other words: the charge efficiency is less than 100%.
3.3.1 About battery capacity and the rate of discharge
The capacity of a battery is rated in ampere-hours (Ah). For example, a lead
acid battery that can deliver a current of 5A during 20 hours is rated at C20 =
100Ah (5 x 20 = 100).
When the same 100Ah battery is discharged completely in two hours, it
may only give C2 = 56Ah (because of the higher rate of discharge).
The BMV takes this phenomenon into account with Peukert’s formula: see
section 5.1.
3.3.2 About charge efficiency (CEF)
The charge efficiency of a lead acid battery is almost 100% as long as no gas
generation takes place. Gassing means that part of the charge current is not
transformed into chemical energy, which is stored in the plates of the battery,
but is used to decompose water into oxygen and hydrogen gas (highly
explosive!). The ‘Amp-hours’ stored in the plates can be retrieved during the
next discharge, whereas the ‘Amp-hours’ used to decompose water are lost.
Gassing can easily be observed in flooded batteries. Please note that the
‘oxygen only’ end of charge phase of sealed (VRLA) gel and AGM batteries
also results in a reduced charge efficiency.
A charge efficiency of 95% means that 10Ah must be transferred to the battery
to get 9,5Ah actually stored in the battery. The charge efficiency of a battery
depends on battery type, age and usage.
The BMV takes this phenomenon into account with the charge efficiency
factor: see section 4.2.2, setting number 06.
3.4 Several battery state-of-charge display options
The BMV can display both the Amp-hours removed (‘consumed Amphours
readout, compensated for charge efficiency only) and the actual state-of-
charge in percent (‘state-of-charge’ readout, compensated for charge
efficiency and Peukert efficiency). Reading the state-of-charge is the best way
to monitor the battery.
The BMV also estimates how long the battery can support the present load:
the ‘time-to-go’ readout. This is the actual the time left until the battery is
discharged to the discharge floor. The factory setting is 50% (see 4.2.2,
setting number 16).
If the load is fluctuating heavily it is best not to rely on this reading too much
since it is a momentary readout and must be used as a guideline only. We
always encourage the use of the state-of-charge readout for accurate battery
monitoring.
3.5 History data
The BMV stores events which can be used at a later date to evaluate usage
patterns and battery health.
Select the history data menu by pressing ENTER when in normal mode (see
section 4.3).

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3.6 Use of alternative shunts
The BMV is supplied with a 500A / 50mV shunt. For most applications, this
should be suitable; however the BMV can be configured to work with a wide
range of different shunts. Shunts of up to 9999A, and/or 75mV can be used.
When using a shunt other than the one supplied with the BMV, please proceed
as follows:
1. Unscrew the PCB from the supplied shunt.
2. Mount the PCB on the new shunt, ensuring that there is good electrical
contact between the PCB and the shunt.
3. Connect the shunt and BMV as shown in the quick installation guide.
4. Follow the Setup wizard (section 1.1 and 1.2).
5. After completion of the Setup wizard, set the proper shunt current and
shunt voltage according to section 4.2.5, setting number 65 and 66.
6. If the BMV reads a non-zero current even when there is no load and the
battery is not being charged: calibrate the zero current reading (see section
4.2.1, setting number 09).
3.7 Automatic detection of nominal system voltage
The BMV will automatically adjust itself to the nominal voltage of the battery
bank, immediately after completion of the setup wizard.
The following table shows how the nominal voltage is determined, and how
the charged voltage parameter (see section 2.2) is adjusted as a result.
BMV-700 & 702
Measured
voltage (V)
Assumed nominal
voltage (V)
Charged Voltage
(V)
<18 12 13.2
18-36 24 26.4
>36 48 52.2
BMV-700H Default nominal voltage: 144V Default: 158,4V
In case of another nominal battery bank voltage (32V for example), the
Charged Voltage must be set manually: see section 4.2.1, setting 02.
Recommended settings:
Nominal battery voltage Recommended Charged Voltage setting
12V 13,2V
24V 26,4V
36V 39,6V
48V 52,8V
60V 66V
120V 132V
144V 158,4V
288V 316,8V
3.8 Alarm, buzzer and relay
On most of the BMV’s readings an alarm can be triggered when the value
reaches a set threshold. When the alarm becomes active the buzzer starts to
beep, the backlight flashes and the alarm icon is visible in the display along
with the current value.
The corresponding segment will also flash. AUX when a starter alarm
occurs. MAIN,MID or TEMP for the corresponding alarm.
(When in the setup menu and an alarm occurs, the value causing the alarm will
not be visible.)
An alarm is acknowledged when a button is pressed. However, the alarm icon
is displayed as long as the alarm condition remains.
It is also possible to trigger the relay when an alarm condition occurs.
The relay contact is open when the coil is de-energized (NO contact), and will
close when the relay is energized.
Factory default setting: the relay is controlled by the state-of-charge of the
battery bank. The relay will be energized when the state-of-charge decreases
to less than 50% (the ‘discharge floor’), and will be deenergized when the
battery has been recharged to 90% state-of-charge. See section 4.2.2.
The relay function can be inverted: de-energized becomes energized and vice
versa. See section 4.2.2.
When the relay is energized, the current drawn by the BMV will increase
slightly: see technical data.

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3.9 Interface options
3.9.1 PC Software BMV-Reader
BMV-Reader will show all current readings on a computer, including history
data. It can also log the data to a CSV formatted file. It is available for free, and
can be downloaded from our website at the Support & Downloads section.
Connect the BMV to the computer with the VE.Direct to USB interface,
ASS030530000.
3.9.2 Large display and remote monitoring
The Color Control GX, a display featuring a 4.3” colour display, provides
intuitive control and monitoring for all products connected to it. The list of
Fangpusun products that can be connected are endless: Inverters, Multis,
Quattros, MPPT solar chargers, BMV-600, BMV-700, Skylla-i, Lynx Ion and
more. The BMV can be connected to the Color Control GX with a VE.Direct
cable. It is also possible to connect it with the VE.Direct to USB interface.
Besides monitoring and controlling locally with the Color Control GX, the
information is also forwarded to our free remote monitoring website: the VRM
Online Portal. For more information, see the Color Control GX documentation
on our website.
3.9.3 Custom integration (programming required)
The VE.Direct communications port can be used to read data and change
settings. The VE.Direct protocol is extremely simple to implement.
Transmitting data to the BMV is not necessary for simple applications: the
BMV automatically sends all readings every second. All the details are
explained in this document:
http://www.fangpusun.com
3.10 Additional functionality of the BMV-702
In addition to the comprehensive monitoring of the main battery system, the
BMV-702 provides a second monitoring input. This secondary input has three
configurable options, described below.
3.10.1 Auxiliary battery monitoring
Wiring diagram: see the quick installation guide. Fig 3
This configuration provides basic monitoring of a second battery, displaying
its voltage. This is useful for systems with a separate starter battery.
3.10.2 Battery temperature monitoring
Wiring diagram: see the quick installation guide. Fig 4
The cable with integrated temperature sensor has to be purchased separately
(part no: ASS000100000). This temperature sensor is not interchangeable
with other Fangpusun temperature sensors, as provided with Multis or battery
chargers. The temperature sensor must be connected to the positive pole of
the battery bank (one of the two wires of the sensor doubles as the power
supply wire).
The temperature can be displayed in degrees Celsius or degrees Fahrenheit,
see section 4.2.5, setting number 67.
The temperature measurement can also be used to adjust battery capacity to
temperature, see section 4.2.5, setting number 68.
The available battery capacity decreases with temperature. Typically, the
reduction, compared to the capacity at 20°C, is 18% at 0°C and 40% at -
20°C.
3.10.3 Midpoint voltage monitoring
Wiring diagram: see the quick installation guide. Fig 5 - 12
One bad cell or one bad battery can destroy a large, expensive battery bank.
A short circuit or high internal leakage current in one cell for example will result
in under charge of that cell and over charge of the other cells.
Similarly, one bad battery in a 24V or 48V bank of several series/parallel
connected 12V batteries can destroy the whole bank.
Moreover, when cells or batteries are connected in series, they should all have
the same initial state-of-charge. Small differences will be ironed out during
absorption or equalise charging, but large differences will result in damage
during charging due to excessive gassing of the cells or batteries with the
highest initial state-of-charge.
A timely alarm can be generated by monitoring the midpoint of the battery
bank. For more information, see section 5.1.

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4 FULL SETUP DETAILS
4.1 Using the menus
Four buttons control the BMV. The function of the buttons depends on which
mode the BMV is in.
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If backlight is off, press any button to restore backlight
Button Function
When in normal mode When in setup mode
Press and hold for two
seconds to switch to setup
mode.
The display will scroll the
number and description of
the selected parameter.
Press SETUP at any time to return to the
scrolling text, and press again to return
to normal mode.
When pressing SETUP while a parameter
is out of range, the display blinks 5 times
and the nearest valid value is displayed.
SETUP
Press to switch to history
menu.
Press to stop scrolling and
show the value. Press
again to switch
back to normal mode.
- Press to stop scrolling after entering the
setup mode with the SETUP button.
- After editing the last digit, press to end
editing. The value is stored automatically.
Confirmation is indicated by a short beep.
- If required, press again to restart editing.
SELECT
Press and hold both SETUP and
SELECT buttons simultaneously
for three seconds to restore
factory settings (disabled when
setting 64, lock setup, is on,
see section 4.2.5)
SETUP/
SELECT
When not editing, press to move up to the
previous parameter.
When editing, this button will increment
the value of the selected digit.
+
_
Move upwards
When not editing, press to move down to
the next parameter.
When editing, this button will decrement
the value of the selected digit.
Move downwards
Press and hold both buttons
simultaneously for three seconds
to manually synchronise the BMV
When power is applied for the first time or when factory settings have been
restored, the BMV will start the quick setup wizard: see section 1. Thereafter,
if power is applied, the BMV will start in normal mode: see section 2.
4.2 Functions overview
The following summary describes all the parameters of the BMV.
- Press SETUP for two seconds to access these functions and use the + and –
buttons to browse them.
- Press SELECT to access the desired parameter.
- Use SELECT and the + and – buttons to customize. A short beep confirms
the setting.
- Press SETUP at any time to return to the scrolling text, and press again to
return to normal mode.
4.2.1 Battery settings
01. Battery capacity
Battery capacity in amp hours
Default Range Step size
200Ah 1 – 9999Ah 1Ah
02. Charged Voltage
The battery voltage must be above this voltage level to consider the battery as
fully charged. The charged-voltage-parameter should always be slightly
below the end of charge voltage of the charger (usually 0.2V or 0.3V below the
‘float’ voltage of the charger). See section 3.7 for recommended settings.
BMV-700 / BMV-702
Default Range Step size
See table, sect 3.7 0 – 95V 0,1V
BMV-700H
Default Range Step size
158,4V 0 – 384V 0,1V
03. Tail current
Once the charge current has dropped to less than the set tail current
(expressed as percentage of the battery capacity), the battery is considered as
fully charged.
Remark:
Some battery chargers stop charging when the current drops below a set
threshold. The tail current must be set higher than this threshold.
Default Range Step size
4% 0,5 – 10% 0,1%

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04. Charged detection time
This is the time the charged-parameters (Charged Voltage and Tail Current)
must be met in order to consider the battery fully charged.
Default Range Step size
3 minutes 1 – 50 minutes 1 minute
05. Peukert exponent
When unknown it is recommended to keep this value at 1,25 for lead acid
batteries and 1,05 for Li-ion batteries. A value of 1,00 disables the Peukert
compensation.
Default Range Step size
1,25 1 – 1,5 0,01
06. Charge Efficiency Factor
The Charge Efficiency Factor compensates for the Ah losses during charging.
100% means no loss.
Default Range Step size
95% 50 – 100% 1%
07. Current threshold
When the current measured falls below this value it will be considered zero.
The current threshold is used to cancel out very small currents that can
negatively affect the long term state-of-charge readout in noisy environments.
For example if the actual long term current is 0,0A and due to injected noise or
small offsets the battery monitor measures 0,05A, and in the long term the
BMV can incorrectly indicate that the battery needs recharging. When the
current threshold in this example is set to 0,1A, the BMV calculates with 0,0A
so that errors are eliminated. A value of 0,0A disables this function.
Default Range Step size
0,1A 0 – 2A 0,01A
08. Time-to-go averaging period
Specifies the time window (in minutes) that the moving averaging filter works.
A value of 0 disables the filter and gives an instantaneous (real-time) readout;
however the displayed value may fluctuate heavily. Selecting the longest time
(12 minutes) ensures that only long term load fluctuations are included in the
time-to-go calculations.
Default Range Step size
3 minutes 0 – 12 minutes 1 minute
09. Zero current calibration
If the BMV reads a non-zero current even when there is no load and the battery is
not being charged, this option can be used to calibrate the zero reading.
Ensure that there really is no current flowing into or out of the battery
(disconnect the cable between the load and the shunt), then press SELECT.
10. Synchronize
This option can be used to manually synchronize the BMV. Press SELECT to
synchronize. The BMV can also be synchronized when in normal operating
mode by holding the + and – buttons simultaneously for 3 seconds.
4.2.2 Relay settings
Remark: thresholds are disabled when set at 0
11. Relay mode
DFLT Default mode. The relay thresholds Nos. 16 up to 31 can be used to
control the relay. CHRG Charger mode. The relay will close when the state-of-
charge falls below setting 16 (discharge floor) or when the battery voltage falls
below setting 18 (low voltage relay). The relay will be open when the state-of-
charge is higher than setting 17 (clear state-ofcharge relay) and the battery
voltage is higher than setting 19 (clear low voltage relay). Application example:
start and stop control of a generator, together with settings 14 and 15. REM
Remote control of the relay. In this mode the relay can be controlled by another
device, for example the Color Control GX.
12. Invert relay
This function enables selection between a normally de-energized (contact
open) or a normally energized (contact closed) relay. When inverted, the open
and closed conditions as described in setting 11 (DFLT and CHRG), and
settings 14 up to 31 are inverted. The normally energized setting will slightly
increase supply current in the normal operating mode.
Default Range
OFF: Normally de-energized OFF: Normally de-energized / ON: normally energized
13. Relay state (read only)
Displays whether the relay is open or closed (de-energized or energized).
Range
OPEN/CLSD
14. Relay minimum closed time
Sets the minimum amount of time that the CLOSED condition will remain
present after the relay has been energized. (changes to OPEN and de
energized if the relay function has been inverted) Application example: set a
minimum generator run time (relay in CHRG mode).
15. Relay-off delay
Sets the amount of time the ‘de-energize relay’ condition must be present
before the relay opens. Application example: keep a generator running for a
while to better charge the battery (relay in CHRG mode).

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Default Range Step size
0 minutes 0 – 500 minutes 1 minute
16. SOC relay (Discharge floor)
When the state-of-charge percentage has fallen below this value, the relay will
close. The time-to-go displayed is the time to reach the discharge floor.
Default Range Step size
50% 0 – 99% 1%
17. Clear SOC relay
When the state-of-charge percentage has risen above this value, the relay will
open (after a delay, depending on setting 14 and/or 15). This value needs to
be greater than the previous parameter setting. When the value is equal to the
previous parameter the state-of-charge percentage will not close the relay.
Default Range Step size
90% 0 – 99% 1%
18. Low voltage relay
When the battery voltage falls below this value for more than 10 seconds the
relay will close.
19. Clear low voltage relay
When the battery voltage rises above this value, the relay will open (after a
delay,depending on setting 14 and/or 15). This value needs to be greater than
or equal to theprevious parameter.
20. High voltage relay
When the battery voltage rises above this value for more than 10 seconds the
relay will close.
21. Clear high voltage relay
When the battery voltage falls below this value, the relay will open (after a
delay, depending on setting 14 and/or 15). This value needs to be less than or
equal to the previous parameter.
BMV-700 / BMV-702
Default Range Step size
0V 0 – 95V 0,1V
BMV-700H
Default Range Step size
0V 0 – 384V 0,1V
22. Low starter voltage relay - 702 only
When the auxiliary (e.g. starter battery) voltage falls below this value for more
than 10 seconds the relay will be activated.
23. Clear low starter voltage relay - 702 only
When the auxiliary voltage rises above this value, the relay will open (after a
delay,depending on setting 14 and/or 15). This value needs to be greater than or
equal to the previous parameter.
24. High starter voltage relay - 702 only
When the auxiliary (e.g. starter battery) voltage rises above this value for more
than 10 seconds, the relay will be activated.
25. Clear high starter voltage relay - 702 only
When the auxiliary voltage falls below this value, the relay will open (after a delay,
depending on setting 14 and/or 15). This value needs to be less than or equal to
the previous parameter.
Default Range Step size
0V 0 – 95V 0,1V
26. High temperature relay - 702 only
When the battery temperature rises above this value for more than 10 seconds,
the relay will be activated.
27. Clear high temperature relay - 702 only
When the temperature falls below this value, the relay will open (after a delay,
depending on setting 14 and/or 15). This value needs to be less than or equal to
the previous parameter.
28. Low temperature relay - 702 only
When the temperature falls below this value for more than 10 seconds, the relay
will be activated.
29. Clear low temperature relay - 702 only
When the temperature rises above this value, the relay will open (after a delay,
depending on setting 14 and/or 15). This value needs to be greater than or equal
to the previous parameter. See setting 67 for choosing between °C and °F.
Default Range Step size
0°C -99 – 99°C 1°C
0°F -146 – 210°F 1°F
30. Mid voltage relay - 702 only
When the mid-point voltage deviation rises above this value for more than 10
seconds, the relay will be activated. See section 5.2 for more information about
the mid-point voltage.
31. Clear mid voltage relay - 702 only
When the mid-point voltage deviation falls below this value, the relay will open
(after a delay, depending on setting 14 and/or 15). This value needs to be less
than or equal to the previous parameter.
Default Range Step size
0% 0 – 99% 0,1%

23 24
4.2.3 Alarm-Buzzer settings
Remark: thresholds are disabled when set at 0
32. Alarm buzzer
When set, the buzzer will sound an alarm. After a button is pressed the buzzer
will stop sounding. When disabled the buzzer will not sound an alarm.
Default Range
ON ON/OFF
33. Low SOC alarm
When the state-of-charge falls below this value for more than 10 seconds the
low SOC alarm is turned on. This is a visual and audible alarm. It does not
energize the relay.
34. Clear low SOC alarm
When the state-of-charge rises above this value, the alarm is turned off. This
value needs to be greater than or equal to the previous parameter.
Default Range Step size
0% 0 – 99% 1%
35. Low voltage alarm
When the battery voltage falls below this value for more than 10 seconds the
low voltage alarm is turned on. This is a visual and audible alarm. It does not
energize the relay.
36. Clear low voltage alarm
When the battery voltage rises above this value, the alarm is turned off. This
value needs to be greater than or equal to the previous parameter.
37. High voltage alarm -When the battery voltage rises above this value for
more than 10 seconds the high voltage alarm is turned on. This is a visual and
audible alarm. It does not energize the relay.
38. Clear high voltage alarm - When the battery voltage falls below this
value, the alarm is turned off. This value needs to be less than or equal to the
previous parameter.
BMV-700 / BMV-702
Default Range Step size
0V 0 – 95V 0,1V
BMV-700H
Default Range Step size
0V 0 – 384V 0,1V
39. Low starter voltage alarm - 702 only
When the auxiliary (e.g. starter battery) voltage falls below this value for more
than 10 seconds the alarm will be activated. This is a visual and audible alarm.
It does not energize the relay.
40. Clear low starter voltage alarm - 702 only
When the auxiliary voltage rises above this value, the alarm is switched off. This
value needs to be greater than or equal to the previous parameter.
41. High starter voltage alarm - 702 only
When the auxiliary (e.g. starter battery) voltage rises above this value for more
than 10 seconds, the alarm will be activated. This is a visual and audible alarm.
It does not energize the relay.
42. Clear high starter voltage alarm - 702 only
When the auxiliary voltage falls below this value, the alarm is switched off. This
value needs to be less than or equal to the previous parameter.
Default Range Step size
0 V 0 – 95 V 0,1 V
43. High temperature alarm - 702 only
When the battery temperature rises above this value for more than 10 seconds,
the alarm will be activated. This is a visual and audible alarm. It does not
energize the relay.
44. Clear high temperature alarm - 702 only
When the temperature falls below this value, the alarm is switched off. This
value needs to be less than or equal to the previous parameter.
45. Low temperature alarm - 702 only
When the temperature falls below this value for more than 10 seconds, the
alarm will be activated. This is a visual and audible alarm. It does not energize
the relay.
46. Clear low temperature alarm - 702 only
When the temperature rises above this value, the alarm is switched off. This
value needs to be greater than or equal to the previous parameter.
See parameter 67 for choosing between °C and °F.
Default Range Step size
0°C -99 – 99°C 1°C
0°F -146 – 210°F 1°F

25 26
47. Mid voltage alarm - 702 only
When the mid-point voltage deviation rises above this value for more than 10
seconds, the alarm will be activated. This is a visual and audible alarm. It does
not energize the relay. See section 5.2 for more information about midpoint
voltage.
Default Range Step size
2% 0 – 99% 0,1%
48. Clear mid voltage alarm - 702 only
When the mid-point voltage deviation falls below this value, the alarm is
switched off. This value needs to be less than or equal to the previous
parameter.
Default Range Step size
1,5% 0 – 99% 0,1%
4.2.4 Display settings
49. Backlight intensity
The intensity of the backlight, ranging from 0 (always off) to 9 (maximum
intensity
Default Range Step size
5 0 – 9 1
50. Backlight always on
When set the backlight will not automatically turn off after 60 seconds of
inactivity.
Default Range
OFF OFF/ON
51. Scroll speed
The scroll speed of the display, ranging from 1 (very slow) to 5 (very fast).
Default Range Step size
2 1 – 5 1
52. Main voltage display
Must be ON to display the voltage of the main battery in the monitoring menu.
53. Current display
Must be ON to display current in the monitoring menu.
54. Power display
Must be ON to display power in the monitoring menu.
55. Consumed Ah display
Must be ON to display consumed Ah in the monitoring menu.
56. State-of-charge display
Must be ON to display state-of-charge in the monitoring menu.
57. Time-to-go display
Must be ON to display time-to-go in the monitoring menu.
58 Starter voltage display - 702 only
Must be ON to display the auxiliary voltage in the monitoring menu.
59. Temperature display - 702 only
Must be ON to display the temperature in the monitoring menu.
60. Mid-voltage display - 702 only
Must be ON to display the mid-point voltage in the monitoring menu.
Default Range
ON ON/OFF
4.2.5 Miscellaneous
61. Software version (read only)
The software version of the BMV
62. Restore defaults
Resets all settings to factory default by pressing SELECT.When in normal
operating mode, factory settings can be restored by pressing SETUP and
SELECT simultaneously for 3 seconds (only if setting 64, Lock setup, is off).
63. Clear history
Clears all history data by pressing SELECT.
64. Lock setup
When on, all settings (except this one) are locked and cannot be altered.
Default Range
OFF OFF/ON
65. Shunt current
When using a shunt other than the one supplied with the BMV, set to the rated
current of the shunt.
Default Range Step size
500A 1 – 9999A 1A
66. Shunt voltage
When using a shunt other than the one supplied with the BMV, set to the rated
voltage of the shunt.
Default Range Step size
50mV 1mV– 75mV 1mV

27 28
67. Temperature unit
CELC Displays the temperature in °C.
FAHR Displays the temperature in °F.
Default Range
CELC CELC/FAHR
68. Temperature coefficient
This is the percentage the battery capacity changes with temperature, when
temperature decreases to less than 20°C (above 20°C the influence of
temperature on capacity is relatively low and is not taken into account). The
unit of this value is “%cap/°C” or percent capacity per degree Celsius. The
typical value (below 20°C) is 1%cap/°C for lead acid batteries, and 0,5%cap/°
C for Lithium Iron Phosphate batteries.
Default Range Step size
0%cap/°C 0 – 2%cap/°C 0,1%cap/°C
69. Aux input
Sets the function of the auxiliary input:
START Auxiliary voltage, e.g. a starter battery.
MID Mid-point voltage.
TEMP Battery temperature.
The cable with integrated temperature sensor has to be purchased separately
(part no: ASS000100000). This temperature sensor is not interchangeable
with other Fangpusun temperature sensors, as provided with Multis or battery
chargers.
4.3 History data
The BMV tracks several parameters regarding the state of the battery which
can be used to evaluate usage patterns and battery health.
Enter history data by pressing the SELECT button when in normal mode.
Press + or – to browse the various parameters.
Press SELECT again to stop scrolling and show the value.
Press + or – to browse the various values.
Press SELECT again to leave the historical menu and go back to normal
operation mode.
The history data is stored in non-volatile memory, and will not be lost
when the power supply to the BMV is interrupted.
The largest value recorded for Ah consumed
since the last synchronisation.
Parameter Description
The deepest discharge in Ah.
Average discharge depth
The number of full discharges. A full
discharge is counted when the state of
charge reaches 0%.
The number of charge cycles. A charge cycle
is counted every time the state-of-charge
drops below 65%, then rises above 90%
The cumulative number of Amp hours
drawn from the battery.
The lowest battery voltage.
The highest battery voltage.
The number of days since the last full charge
The number of automatic synchronisations
The number of low voltage alarms.
The number of high voltage alarms.
The lowest auxiliary battery voltage.
The highest auxiliary battery voltage.
The total amount of energy drawn from the
battery in (k)Wh
The total amount of energy absorbed by the
battery in (k)Wh
* BMV-702 only

29 30
5 MORE ABOUT PEUKERT’S FORMULA AND MIDPOINT
MONITORING
5.1 Peukert’s formula: battery capacity and discharge rate
The value which can be adjusted in Peukert’s formula is the exponent n:
see the formula below.
In the BMV Peukert’s exponent can be adjusted from 1.00 to 1.50. The higher
the Peukert exponent the faster the effective capacity ‘shrinks’ with increasing
discharge rate. An ideal (theoretical) battery has a Peukert Exponent of 1.00
and has a fixed capacity; regardless of the size of the discharge current. The
default setting for the Peukert exponent is 1.25. This is an acceptable average
value for most lead acid batteries. Peukert’s equation is stated below:
The battery specifications needed for calculation of the Peukert exponent are
the rated battery capacity (usually the 20 h discharge rate ) and for example a
5h discharge rate . See below for an example of how to calculate the Peukert
exponent using these two specifications.
5h rating
1
2
1 Please note that the rated battery capacity can also be the 10h or even 5h
discharge rate.
2 The 5h discharge rate in this example is just arbitrary. Make sure that
besides the C20 rating (low discharge current) a second rating with a
substantially higher discharge current is chosen.
A Peukert calculator is available at
http://www.fangpusun.com
Please note that Peukert’s formula is no more than a rough approximation of
reality, and that at very high currents, batteries will give even less capacity than
predicted from a fixed exponent.
We recommend not to change the default value in the BMV, except in case of
Li-ion batteries: See section 6.
5.2 Midpoint voltage monitoring
Wiring diagram: see the quick installation sheet. Fig 5-12
One bad cell or one bad battery can destroy a large, expensive battery bank.
A short circuit or high internal leakage current in one cell for example will result
in under charge of that cell and over charge of the other cells.
Similarly, one bad battery in a 24V or 48V bank of several series/parallel
connected 12V batteries can destroy the whole bank.
Moreover, when new cells or batteries are connected in series, they should all
have the same initial state-of-charge. Small differences will be ironed out
during absorption or equalise charging, but large differences will result in
damage during charging due to excessive gassing of the cells or batteries with
the highest initial state-of-charge.

31 32
A timely alarm can be generated by monitoring the midpoint of the battery
bank (i. e. by splitting the string voltage in half and comparing the two string
voltage halves).
Please note that the midpoint deviation will be small when the battery bank is
at rest, and will increase:
a) at the end of the bulk phase during charging (the voltage of well charged
cells will increase rapidly while lagging cells still need more charging),
b) when discharging the battery bank until the voltage of the weakest cells
starts to decrease rapidly, and
c) at high charge and discharge rates.
5.2.1 How the % midpoint deviation is calculated
d (%) = 100*(Vt – Vb) / V
d is the deviation in %
Vt is the top string voltage
Vb is the bottom string voltage
V is the voltage of the battery (V = Vt + Vb)
5.2.2 Setting the alarm level:
In case of VRLA (gel or AGM) batteries, gassing due to overcharging will dry
out the electrolyte, increasing internal resistance and ultimately resulting in
irreversible damage. Flat plate VRLA batteries start to lose water when the
charge voltage approaches 15V (12V battery).
Including a safety margin, the midpoint deviation should therefore remain
below 2% during charging.
When, for example, charging a 24V battery bank at 28,8V absorption voltage,
a midpoint deviation of 2% would result in:
Vt = V*d/100* + Vb = V*d/100 + V – Vt
:
Vt = (V*(1+d/100) / 2 = 28,8*1,02 / 2 ≈ 14,7V
Vb = (V*(1-d/100) / 2 = 28,8*0,98 / 2 ≈ 14,1V
Obviously, a midpoint deviation of more than 2% will result in overcharging
the top battery and undercharging the bottom battery.
Two good reasons to set the midpoint alarm level at not more than d = 2%.
where:
Therefore
And:
This same percentage can be applied to a 12V battery bank with a 6V midpoint.
In case of a 48V battery bank consisting of 12V series connected batteries,the
% influence of one battery on the midpoint is reduced by half. The midpoint
alarm level can therefore be set at a lower level.
5.2.3 Alarm delay
In order to prevent the occurrence of alarms due to short term deviations that
will not damage a battery, the deviation must exceed the set value during 5
minutes before the alarm is triggered.
A deviation exceeding the set value by a factor of two or more will trigger the
alarm after 10 seconds.
5.2.4 What to do in case of an alarm during charging
In case of a new battery bank the alarm is probably due to differences in initial
state-of-charge. If d increases to more than 3%: stop charging and charge the
individual batteries or cells separately first, or reduce charge current
substantially and allow the batteries to equalize over time.
If the problem persists after several charge-discharge cycles:
a) In case of series-parallel connection disconnect the midpoint parallel
connection wiring and measure the individual midpoint voltages during
absorption charging to isolate batteries or cells which need additional
charging.
b) Charge and then test all batteries or cells individually.
In case of an older battery bank which has performed well in the past, the
problem may be due to:
a) Systematic under charge, more frequent charging or equalization charge
needed (flooded deep cycle flat plate or OPzS batteries). Better and regular
charging will solve the problem.
b) One or more faulty cells: proceed as suggested under a) or b).

33 34
5.2.5 What to do in case of an alarm during discharging
The individual batteries or cells of a battery bank are not identical, and when
fully discharging a battery bank the voltage of some cells will start dropping
earlier than others. The midpoint alarm will therefore nearly always trip at the
end of a deep discharge.
If the midpoint alarm trips much earlier (and does not trip during charging),
some batteries or cells may have lost capacity or may have developed a
higher internal resistance than others. The battery bank may have reached
the end of service life, or one of more cells or batteries have developed a fault:
a) In case of series-parallel connection, disconnect the midpoint parallel
connection wiring and measure the individual midpoint voltages during
discharging to isolate faulty batteries or cells.
b) Charge and then test all batteries or cells individually.
6 LITHIUM IRON PHOSPHATE BATTERIES (LiFePO4)
A residual discharge current is especially dangerous if the system has
been discharged completely and a low cell voltage shut down has
occurred. After shutdown due to low cell voltage, a capacity reserve of
approximately 1Ah per 100Ah battery capacity is left in a Li-ion battery.
The battery will be damaged if the remaining capacity reserve is drawn
from the battery. A residual current of 4mA for example may damage a
100Ah battery if the system is left in discharged state during more than
10 days (4mA x 24h x 10 days = 0,96Ah).
A BMV draws 4mA from a 12V battery. The positive supply must
therefore be interrupted if a system with Li-ion batteries is left
unattended during a period long enough for the current draw by the
BMV to completely discharge the battery.
LiFePO4 is the most commonly used Li-ion battery chemistry.
The factory default ‘charged parameters’ are in general also applicable to
LiFePO4 batteries.
Some battery chargers stop charging when the current drops below a set
threshold. The tail current must be set higher than this threshold.
The charge efficiency of Li-ion batteries is much higher than of lead acid
batteries: We recommend to set the charge efficiency at 99%.
When subjected to high discharge rates, LiFePO4 batteries perform much
better than lead-acid batteries. Unless the battery supplier advizes otherwise,
we recommend setting Peukert’s exponent at 1.05.
Important warning
Li-ion batteries are expensive and can be irreparably damaged due to over
discharge or over charge.
Damage due to over discharge can occur if small loads (such as: alarm
systems, relays, standby current of certain loads, back current drain of battery
chargers or charge regulators) slowly discharge the battery when the system is
not in use.
In case of any doubt about possible residual current draw, isolate the battery
by opening the battery switch, pulling the battery fuse(s) or disconnecting the
battery positive when the system is not in use.

35
7 DISPLAY
A:
B:
C:
D:
E:
F:
G:
H:
I :
J:
K:
L:
M:
Scrolling
Overview of the BMV’s display
The value of the selected item is displayed with these digits
Colon
Decimal separator
Main battery voltage icon
Battery temperature icon
Auxiliary voltage icon
Mid-point voltage icon
Setup menu active
History menu active
Battery needs to be recharged (solid), or BMV is not synchronized
(blinking, together with K)
Battery state-of-charge indicator (blinks when not synchronized)
Unit of the selected item. e.g. W, kW, kWh, h, V, %, A, Ah, °C, °F
Alarm indicator
The BMV features a scrolling mechanism for long texts. The scroll speed can
be changed by modifying the setting scroll speed in the settings menu. See
section 4.2.4. parameter 51
8 TECHNICAL DATA
Supply voltage range (BMV-700 / BMV-702) 6.5 … 95 VDC
Supply voltage range (BMV-700H) 60… 385 VDC
Supply current (no alarm condition, backlight off)
BMV-700/BMV-702
@Vin = 12 VDC 4mA
With relay energized 15mA
@Vin = 24 VDC 3mA
With relay energized 8mA
BMV-700H
@Vin = 144 VDC 3mA
@Vin = 288 VDC 3mA
Input voltage range auxiliary battery (BMV-702) 0 ... 95 VDC
Input current range (with supplied shunt) -500 ... +500A
Operating temperature range -20 ... +50°C
Readout resolution:
Voltage (0 ... 100V) ±0.01V
Voltage (100 … 385V) ±0.1V
Current (0 ... 10A) ±0.01A
Current (10 ... 500A) ±0.1A
Current (500 ... 9999A) ±1A
Amp hours (0 ... 100Ah) ±0.1Ah
Amp hours (100 ... 9999Ah) ±1Ah
State-of-charge (0 ... 100%) ±0.1%
Time-to-go (0 ... 1h) ±0.1h
Time-to-go (1 ... 240h) ±1h
Temperature ±1°C/°F
Power (-100 ... 1kW) ±1W
Power (-100 ... 1kW) ±1kW
Voltage measurement accuracy ±0.3%
Current measurement accuracy ±0.4%
Potential free contact
Mode Configurable
Default mode Normally open
Rating 60V/1A max.
Dimensions:
Front panel 69 x 69mm
Body diameter 52mm
Overall depth 31mm
Net weight:
BMV 70g
Shunt 315g
Material
Body ABS
Sticker Polyester 36