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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•
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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%