MPPT M32-10 User manual

MPPT Solar Charge Controller
User Manual
Models:
M32-10, 10A, 12/24V
M32-20, 20A,12/24V
M32-30, 30A,12/24V
M32-40, 40A,12/24V

Important Safety Instructions
Please keep this manual for future review.
This manual contains all instructions of safety, installation and operation for Maximum
Power Point Tracking (MPPT) controller ("the controller" as referred to in this manual).
General Safety Information
Read carefully all the instructions and warnings in the manual before installation.
No user serviceable components inside the controller. DO NOT disassemble or
attempt to repair the controller.
Mount the controller indoors. Avoid exposure the components and do not allow
water to enter the controller.
Install the controller in a well-ventilated place. The controller’s heat sink may
become very hot during operation.
Suggest installing appropriate external fuses/breakers.
Make sure to switch off all PV array connections and the battery fuse/breakers
before controller installation and adjustment.
Power connections must remain tight to avoid excessive heating from loose
connection.

CONTENTS
1. General Information........................................................................1
1.1 Overview.............................................. 1
1.2 Characteristics......................................... 2
1.3 Naming Rules of Controller models ....................... 2
1.4Product Classification ................................... 3
2. Installation Instructions .................................................................4
2.1 General Installation Notes ............................... 4
2.2 PV Array Requirements ................................. 4
2.3 Wire Size ............................................. 6
2.4 Mounting.............................................. 7
3. Display units .................................................................................10
3.1 Adanced Display unit ................................ 10
4. Control Parameters Setting .........................................................15
4.1 Battery types ......................................... 15
4.1.1 Support battery types ............................. 15
4.1.2 Battery Voltage Control Parameters................. 15
4.1.3Settings ......................................... 17
4.2 Load working modes................................... 18
4.2.1LCD setting ...................................... 18
4.2.2R485 communication setting ....................... 19
4.3 Accessories (optional) ................................. 20
5. Protections, Troubleshooting and Maintenance........................21
5.1 Protection............................................ 22
5.2 Troubleshooting....................................... 23
5.3 Maintenance ......................................... 23
6. Technical Specifications..............................................................25
Annex I Conversion Efficiency Curves ...........................................28
Annex II Mechanical Dimension Diagram.......................................33

1
1. General Information
1.1 Overview
The solar charge controller adopts the advanced MPPT control algorithm. It can
minimize the maximum power point loss rate and loss time, quickly track the
maximum power point (MPP) of the PV array and obtain the maximum energy from
solar array under any conditions; and it can increase the ratio of energy utilization in
the solar system by 20%-30% compared with PWM charging method.
Limiting the charging power & current and reducing charging power functions ensure
the system stable with over PV modules in high temperature environment. IP33
Ingress protection and isolated RS485 design further improve the controller’s
reliability and meet the different application requirements.
The controller owns self-adaptive three-stage charging mode based on digital control
circuit, which can effectively prolong the lifespan of battery and significantly improve
the system performance. It also has comprehensive electronic protection for
overcharge, over discharge, PV& battery reverse polarity etc., to ensure the solar
system more reliable and more durable. This controller can be widely used for RV,
household system, field monitoring and many other applications.
Features：
100% charging and discharging in working environment temperature range
Embedded LCD
High quality and low failure rate components of ST or IR to ensure service life
Advanced MPPT technology& ultra-fast tracking speed guarantee tracking
efficiency up to 99.5%
Maximum DC/DC transfer efficiency is as high as 98.5%★, full load efficiency is up
to 97.2%★
Advanced MPPT control algorithm to minimize the MPP lost rate and lost time
Accurate recognizing and tracking of multi-peaks maximum power point
Wide MPP operating voltage range
Support the lead-acid and lithium batteries
Limit charging power & current over rated value
Real-time energy statistics function
Power reduction automatically over temperature value
Multiple load work modes
Comprehensive electronic protection
Isolated RS485 with 5V/200mA output, with Modbus protocol
Support monitoring and setting the parameters via APP or PC software

2
IP33▲Ingress protection
▲3-protection against solid objects: protected against solids objects over
2.5mm.
3-protected against sprays to 60°from the vertical.
1.2 Characteristics
❶
RTS★port
❺
RS485 communication port
❷
PV Terminals
❻
Terminal protection cover
❸
Battery Terminals
❼
Display units
❹
Load Terminals
❽
Mounting Hole Φ5mm
★If the temperature sensor is short circuit or damaged, the controller will
charge or discharge according the voltage setting point at the default
temperature setting of 25 ºC(no temperature compensation).
Figure 1 Product Characteristics

3
1.3 Naming Rules of Controller models
EXAMPLE:
M 3 2-40
1.4Product Classification
Model
Picture
Display
M****
LED Indicators: PV & battery & load
working status
Buttons:View or set the parameters
or clear the error information.
LCD: PV display:voltage/current
/generated energy/power
Battery display:voltage/current/
temperature/capacity
Load display:voltage/current/power
/consumed energy/load working mode
MPPT charging technology
Max PV open circuit voltage:1-25V，2-50V，3-100V, 4-150V
System voltage: 1-12V;
2-12/24V
Charging and discharge current: 40-40A, 30-30A,
20-20A, 10-10A

4
2. Installation Instructions
2.1 General Installation Notes
Please read the entire installation instructions to get familiar with the installation
steps before installation.
Be very careful when installing the batteries, especially flooded lead-acid battery.
Please wear eye protection, and have fresh water available to wash and clean any
contact with battery acid.
Keep the battery away from any metal objects, which may cause short circuit of the
battery.
Explosive battery gases may come out from the battery during charging, so make
sure ventilation condition is good.
Ventilation is highly recommended if mounted in an enclosure. Never install the
controller in a sealed enclosure with flooded batteries! Battery fumes from vented
batteries will corrode and destroy the controller circuits.
Loose power connections and corroded wires may result in high heat that can melt
wire insulation, burn surrounding materials, or even cause fire. Ensure tight
connections and use cable clamps to secure cables and prevent them from swaying
in mobile applications.
The controller can work with lead-acid battery and lithium battery within its control
scope.
Battery connection may be wired to one battery or a bank of batteries. The following
instructions refer to a singular battery, but it is implied that the battery connection
can be made to either one battery or a group of batteries in a battery bank.
Multiple same models of controllers can be installed in parallel on the same battery
bank to achieve higher charging current. Each controller must have its own solar
module(s).
Select the system cables according to 5A/mm2or less current density in accordance
with Article 690 of the National Electrical Code, NFPA 70.
2.2 PV Array Requirements
(1) Serial connection (string) of PV modules
As the core component of solar system, controller could be suitable for various types
of PV modules and maximize converting solar energy into electrical energy. According
to the open circuit voltage (Voc) and the maximum power point voltage (VMpp) of the
MPPT controller, the series number of different types PV modules can be calculated.
The below table is for reference only.

5
M32-10/32-20/32-30/32-40N:
System
voltage
36cell
Voc＜23V
48cell
Voc＜31V
54cell
Voc＜34V
60cell
Voc＜38V
Max.
Best
Max.
Best
Max.
Best
Max.
Best
12V
4
2
2
1
2
1
2
1
24V
4
3
2
2
2
2
2
2
System
voltage
72cell Voc＜46V
96cell Voc＜62V
Thin-Film
Module
Voc＞80V
Max.
Best
Max.
Best
12V
2
1
1
1
1
24V
2
1
1
1
1
NOTE: The above parameter values are calculated under standard test conditions
(STC (Standard Test Condition)：Irradiance 1000W/m2，Module Temperature 25℃，
Air Mass1.5.)
(2) Maximum PV array power
The MPPT controller has the function of charging current/power-limiting, that is,
during the charging process, when the charging current or power exceeds the rated
charging current or power, the controller will automatically limit the charging current or
power to the rated range, which can effectively protect the charging parts of controller,
and prevent damages to the controller due to the connection of some
over-specification PV modules. The actual operation of PV array is as follows:
Condition 1:
Actual charging power of PV array ≤Rated charging power of controller
Condition 2:
Actual charging current of PV array ≤Rated charging current of controller
When the controller operates under “Condition 1”or “Condition 2”, it will carry out
the charging as per the actual current or power; at this time, the controller can work at
the maximum power point of PV array.
WARNING: When the power of PV is not greater than the rated charging
power, but the maximum open-circuit voltage of PV array is more than
100V(at the lowest environmental temperature), the controller may be
damaged.
Condition 3:
Actual charging power of PV array ＞Rated charging power of controller
Condition 4:
Actual charging current of PV array ＞Rated charging current of controller
When the controller operates under “Condition 3”or “Condition 4”，it will carry out
the charging as per the rated current or power.

6
WARNING: When the power of PV module is greater than the rated
charging power, and the maximum open-circuit voltage of PV array is more
than100V (at the lowest environmental temperature), the controller may be
damaged.
According to “Peak Sun Hours diagram”, if the power of PV array exceeds the rated
charging power of controller, then the charging time as per the rated power will be
prolonged, so that more energy can be obtained for charging the battery. However, in
the practical application, the maximum power of PV array shall be not greater than 1.5
x the rated charging power of controller. If the maximum power of PV array exceeds
the rated charging power of controller too much, it will not only cause the waste of PV
modules, but also increase the open-circuit voltage of PV array due to the influence of
environmental temperature, which may make the probability of damage to the
controller rise. Therefore, it is very important to configure the system reasonably. For
the recommended maximum power of PV array for this controller, please refer to the
table below:
Model
Rated Charge
Current
Rated Charge
Power
Max. PV Array
Power
Max. PV open
circuit voltage
M32-10
10A
130W/12V
260W/24V
195W/12V
390W/24V
92V①
100V②
M32-20
20A
260W/12V
520W/24V
390W/12V
780W/24V
M32-30
30A
390W/12V
780W/24V
580W/12V
1170W/24V
M32-40
40A
520W/12V
1040W/24V
780W/12V
1560W/24V
①At 25℃environment temperature
②At minimum operating environment temperature
2.3Wire Size
The wiring and installation methods must conform to all national and local electrical
code requirements.
PV Wire Size
Since PV array output varies due to the PV module size, connection method or
sunlight angle, the minimum wire size can be calculated by the Isc＊of PV array.
Please refer to the value of Isc in the PV module specification. When PV modules
connect in series, the Isc is equal to a PV modules Isc. When PV modules connect in
parallel, the Isc is equal to the sum of Isc of the PV modules. The Isc of the PV array
must not exceed the maximum PV input current of controllers. Please refer to the
table as below:
NOTE: All PV modules in a given array are assumed to be identical.
＊Isc=short circuit current(amps) Voc=open circuit voltage.
Model
Max. PV input current
Max. PV wire size＊

7
M32-10
10A
4mm2/12AWG
M32-20
20A
6mm2/10AWG
M32-30
30A
10mm2/8AWG
M32-40
40A
16mm2/6AWG
＊These are the maximum wire sizes that will fit the controller terminals.
CAUTION: When the PV modules are connected in series, the open circuit
voltage of the PV array must not exceed 92V (M**10), at 25℃environment
temperature.
Battery and Load Wire Size
The battery and load wire size must conform to the rated current, the reference size
as below:
Model
Rated
charge
current
Rated
discharge
current
Battery wire
size
Load wire
size
M32-10
10A
10A
4mm2/12AWG
4mm2/12AWG
M32-20
20A
20A
6mm2/10AWG
6mm2/10AWG
M32-30
30A
30A
10mm2/8AWG
10mm2/8AWG
M32-40
40A
40A
16mm2/6AWG
16mm2/6AWG
CAUTION: The wire size is only for reference. If there is a long distance
between the PV array and the controller or between the controller and the
battery, larger wires can be used to reduce the voltage drop and improve
performance.
CAUTION: For the battery, the recommended wire will be selected
according to the conditions that its terminals are not connected to any
additional inverter.
2.4 Mounting
WARNING: Risk of explosion! Never install the controller in a sealed enclose
with flooded batteries! Do not install in a confined area where battery gas can
accumulate.
WARNING: Risk of electric shock! When wiring the solar modules, the PV
array can produce a high open circuit voltage, so turn off the breaker before
wiring and be careful when wiring.
CAUTION：The controller requires at least 150mm of clearance above and
below for proper air flow. Ventilation is highly recommended if mounted in an

8
enclosure.
Installation Procedure:
Step1: Determination of Installation Location and Heat-dissipation Space
Determination of installation location: The controller shall be installed in a place with
sufficient air flow through the radiators of the controller and a minimum clearance of
150 mm from the upper and lower edges of the controller to ensure natural thermal
convection. Please see Figure 2-1: Mounting
CAUTION: If the controller is to be installed in an enclosed box, it is
important to ensure reliable heat dissipation through the box.
Figure2-1 Mounting

9
Step 2：Connect the system in the order of ❶battery ❷load❸PV array in
accordance with Figure 2-2,” Schematic Wiring Diagram” and disconnect the system
in the reverse order❸❷❶.
CAUTION:While wiring the controller do not close the circuit breaker or fuse
and make sure that the leads of "+" and "-" poles are connected correctly.
CAUTION:A fuse which current is 1.25 to 2 times the rated current of the
controller, must be installed on the battery side with a distance from the
battery not greater than 150 mm.
CAUTION: If the controller is to be used in an area with frequent lightning
strikes or unattended area, it must install an external surge arrester.
CAUTION: If an inverter is to be connected to the system, connect the
inverter directly to the battery, not to the load side of the controller.
Step 3：Grounding
MN series is a common-negative controller, where all the negative terminals of PV
array, battery and load can be grounded simultaneously or any one of them will be
grounded. However, according to the practical application, all the negative terminals
of PV array, battery and load can also be ungrounded, but the grounding terminal on
its shell must be grounded, which may effectively shield the electromagnetic
interference from the outside, and prevent some electric shock to human body due to
the electrification of the shell.
CAUTION: For common-negative system, such as motorhome, it is
recommended to use a common-negative controller; but if in the
common-negative system, some common-positive equipment are used,
and the positive electrode is grounded, the controller may be damaged.
Step 4：Connect accessories
Connect the remote temperature sensor cable
（supply with controller ）
Connect the remote temperature sensor cable to the interface ①and place the other
end close to the battery.
CAUTION: If the remote temperature sensor is not connected to the
controller, the default setting for battery charging or discharging
temperature is 25 °C without temperature compensation.
Figure 2-2 Schematic of wiring diagram
Temperature Sensor
Remote Temperature Sensor
Cable(Optional)

10
Connect the accessories for RS485 communication
Refer to chaper4“Control Parameters Setting”.
Step 5：Powered on the controller
Closing the battery fuse will switch on the controller. Then check the status of the
battery indicator (the controller is operating normally when the indicator is lit in
green).Close the fuse and circuit breaker of the load and PV array. Then the system
will be operating in the preprogrammed mode.
CAUTION:If the controller is not operating properly or the battery indicator
on the controller shows an abnormality, please refer to 5.2
“Troubleshooting”.
3.Display units
3.1Display unit
(1)Indicator
Indicator
Color
Status
Instruction
Green
On Solid
PV connection normal but low
voltage(low irradiance) from
PV, no charging
Green
OFF
No PV voltage(night time) or
PV connection problem
Green
Slowly Flashing(1Hz)
Incharging
Green
Fast Flashing(4Hz)
PV Over voltage

11
Green
On Solid
Normal
Green
Slowly Flashing(1Hz)
Full
Green
Fast Flashing(4Hz)
Over voltage
Orange
On Solid
Under voltage
Red
On Solid
Over discharged
Red
Slowly Flashing(1Hz)
Battery Overheating
Lithium battery Low
temperature①
Yellow
On Solid
Load ON
Yellow
OFF
Load OFF
PV&BATTLED fast flashing
Controller Overheating
System voltage error②
①When a lead-acid battery is used, the controller doesn’t have the low temperature
protection.
②When a lithium battery is used, the system voltage can’t be identified automatically
(2)Button
Press the button
PV browsing interface
Setting data +
Press the button and
hold 5s
Setting the LCD cycle time
Press the button
BATT browsing interface
Cursor displacement during setting
Press the button and
hold 5s
Setting the battery type, battery capacity
level and temperature unit.
Press the button
Controller load browsing interface
Setting data -
Press the button and
hold 5s
Setting the load working mode
Press the button
Enter into setting interface
Setting interface switch to the browsing
interface
Setting parameter as enter button
Press the button
Exit the setting interface
(3)Display

12
Icon
Information
Icon
Information
Icon
Information
Day
Not
charging
Not
discharging
Night
Charging
Discharging
1)PV parameters
Display：Voltage/Current/Power/Generated Energy
2)Battery parameters
Display：Voltage/Current/Temperature/Battery capacitylevel
3)Load parameters

13
Display：Voltage/Current/Power/Consumedenergy/Load working mode-Timer1/ Load
working mode-Timer2
(4)Setting parameters
1)Battery type
Operation:
Step 1: Press the button for the setting interface.
Step 2: Press the button and hold 5s for the battery type interface.
Step 3: Press the or button to choose the battery type.
Step 4: Press the button to confirm the battery type.
CAUTION：Please refer to chapter 4.1 for the battery control voltage
setting, when the battery type is User.
2)Battery capacity
Operation:
Step 1: Press the button for the setting interface.
Step 2: Press the button and hold 5s for the battery type interface.
Step 3: Press the button for the battery capacity interface.
Step 4: Press the or button to set the battery capacity.
Step 5: Press the button to confirm the parameters.
User
Gel
Sealed(Default)
Flooded

14
3)Temperature units
Operation:
Step 1: Press the button for the setting interface.
Step 2: Press the button and hold 5s for the battery type interface.
Step 3: Press the button twice for the temperature unit interface.
Step 4: Press the or button to set the temperature units.
Step 5: Press the button to confirm the parameters.
4)LCD cycle time
NOTE: The LCD cycle default time is 2s,the setting time range is 0～20s.
Operation:
Step 1: Press the button for the setting interface.
Step 2: Press the button and hold 5s for the LCD cycle time interface.
Step 3: Press the or button to set the LCD cycle time.
Step 4: Press the button to confirm the parameters.

15
5)Local load working mode
Operation:
Step 1: Press the button for the setting interface.
Step 2: Press the button and hold 5s for the load working mode interface.
Step 3: Press the or button to set the working mode..
Step 4: Press the button to confirm the parameters.
NOTE：Please refer to chapter 4.2 for the load working mode.
4. Control Parameters Setting
4.1 Battery types
4.1.1 Support battery types
1
Lead-acid battery
Sealed(default)
Gel
Flooded
User
2
Lithium battery
LiFePO4(4S/12V;8S/24V )
Li(NiCoMn)O2(3S/12V;6S/24V )
User
CAUTION: When the default battery type is selected, the battery
voltage control parameters will be set by default and can’t be
changed. To change these parameters, select "User" battery type.
4.1.2 Battery Voltage Control Parameters
Lead-acid battery parameters

16
The parameters are in 12V system at 25 ºC, please double the values in 24V
system.
Battery type
Voltage
Sealed
Gel
Flooded
User
Over Voltage Disconnect
Voltage
16.0V
16.0V
16.0V
9～17V
Charging Limit Voltage
15.0V
15.0V
15.0V
9～17V
Over Voltage Reconnect
Voltage
15.0V
15.0V
15.0V
9～17V
Equalize Charging Voltage
14.6V
——
14.8V
9～17V
Boost Charging Voltage
14.4V
14.2V
14.6V
9～17V
Float Charging Voltage
13.8V
13.8V
13.8V
9～17V
Boost Reconnect Charging
Voltage
13.2V
13.2V
13.2V
9～17V
Low Voltage Reconnect
Voltage
12.6V
12.6V
12.6V
9～17V
Under Voltage Warning
Reconnect Voltage
12.2V
12.2V
12.2V
9～17V
Under Voltage Warning
Voltage
12.0V
12.0V
12.0V
9～17V
Low Voltage Disconnect
Voltage
11.1V
11.1V
11.1V
9～17V
Discharging Limit Voltage
10.6V
10.6V
10.6V
9～17V
Equalize Duration
120 min
——
120 min
0～180 min
Boost Duration
120 min
120 min
120 min
10～180 min
The following rules must be observed when modifying the parameter values in User
for lead-acid battery.
Ⅰ.Over Voltage Disconnect Voltage > Charging Limit Voltage ≥ Equalize Charging
Voltage ≥ Boost Charging Voltage ≥ Float Charging Voltage > Boost Reconnect
Charging Voltage.
Ⅱ. Over Voltage Disconnect Voltage > Over Voltage Reconnect Voltage
Ⅲ. Low Voltage Reconnect Voltage > Low Voltage Disconnect Voltage ≥ Discharging
Limit Voltage.
Ⅳ.Under Voltage Warning Reconnect Voltage > Under Voltage Warning Voltage ≥
Discharging Limit Voltage.
Ⅴ.Boost Reconnect Charging voltage >Low Voltage Reconnect Voltage.
Lithium battery parameters
The parameters are in 12V system at 25 ºC, please double the values in 24V .
Battery type
Voltage
LiFePO4
Li(NiCoMn)O2
User
Over Voltage Disconnect
Voltage
15.6V
13.5V
9～17V
Charging Limit Voltage
14.6V
12.6V
9～17V

17
Over Voltage Reconnect
Voltage
14.7V
12.7V
9～17V
Equalize Charging
Voltage
14.5V
12.5V
9～17V
Boost Charging Voltage
14.5V
12.5V
9～17V
Float Charging Voltage
13.8V
12.2V
9～17V
Boost Reconnect
Charging Voltage
13.2V
12.1V
9～17V
Low Voltage Reconnect
Voltage
12.8V
10.5V
9～17V
Under Voltage Warning
Reconnect Voltage
12.8V
11.0V
9～17V
Under Voltage Warning
Voltage
12.0V
10.5V
9～17V
Low Voltage Disconnect
Voltage
11.1V
9.3V
9～17V
Discharging Limit Voltage
10.6V
9.3V
9～17V
The following rules must be observed when modifying the parameter values in
Userforlithium battery.
Ⅰ. Over Voltage Disconnect Voltage>Over charging protection voltage(Protection
Circuit Modules(BMS))+0.2V※;
Ⅱ. Over Voltage Disconnect Voltage>Over Voltage Reconnect Voltage＝Charging
Limit Voltage ≥ Equalize Charging Voltage＝Boost Charging Voltage ≥ Float
Charging Voltage>Boost Reconnect Charging Voltage;
Ⅲ. Low Voltage Reconnect Voltage>Low Voltage Disconnect Voltage ≥ Discharging
Limit Voltage;
Ⅳ. Under Voltage Warning Reconnect Voltage>Under Voltage Warning Voltage≥
Discharging Limit Voltage;
Ⅴ. Boost Reconnect Charging voltage> Low Voltage Reconnect Voltage;
Ⅵ. Low Voltage Disconnect Voltage ≥ Over discharging protection voltage
(BMS)+0.2V※.
WARNING: The voltage parameters of lithium battery can be set, but you
must refer to the voltage parameters of lithium battery BMS.
WARNING: The required accuracy of BMS shall be at least 0.2V. If the
deviation is higher than 0.2V, the manufacturer will assume no liability for
any system malfunction caused by this.
4.1.3Settings
1) PC setting
Connection