PowerTech MP-3735 User manual

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Operating Manual MP-3735

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About this manual
These operating instructions come with the product and should be kept for the life of the product for proper
installation and usage.
Read these operating instructions carefully before use,
Keep them for the entire life of the product,
And pass then on to any future owner or user of this product.
This manual describesthe installation, function, operation and maintenance of the solar system controller
MP-3735. These operating instructions are intended for end customers. Atechnical expert must be consulted in
cases of uncertainty.
Safety
1. The solar controller may only be used in PV systems for charging and controlling Lead-Acid batteries.
2. No energysource other than solar photovoltaic modules may be connected to the solar charge controller.
3. Use only with 12V or 24V nominal voltage solar PV array
4. Do not connect any defective or damaged measuring equipment.
5. Follow general, safety and accidentprevention regulation.
6. Never alter or remove the factory plates and identification labels.
7. Keep children away from PV systems.
8. Never open the device.
9. Only one solar array can connect with one controller only.
10. Never touch bare cables ends.
Other risks
Danger of fire and explosion
Do not use the solar charge controller in dusty environments, in the vicinity of solvents or where
inflammable gases and vapour can occur.
No open fires, flames or sparks in the vicinity of the batteries.
Ensure that the room is adequately ventilated.
Check the charging process regularly.
Follow the charging instructions of the battery manufacturer.
Battery acid
Acid splashes on skin or clothing should be immediately treated with soap suds and rinsed with
plenty of water.
If acid splashes into the eyes, immediately rinse with plenty of water. Seek medical advice.

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Fault behaviour
Operating the solar charge controller is dangerous in the following situations:
The solar charge controller does not appearto function at all
The solar charge controller or connected cables are visibly damaged
Emission of smoke or fluid penetration
When parts are loose
In these cases immediately remove the solar charge controller from the solar panels and battery.
Function
The solar system controller, MP-3735 carries the following features:
Monitors the state of charge of the battery
Controls the charging process
Controls the connection/disconnection of loads
Make sure Solar system works in proper manner
Programmable Bulk and Float charge voltage
Night-Light Function
Temperature Compensation
Manual load switch with automatic re-start.
Twotimerscheduleprogrammable
MPPTtechnology, capturing moreenergyfromsun
Whatis MPPtracking (MPPT)?
MPPTstandsfor"MaximumPowerPointTracking".Thisdescribesaprocessby meansof
which the solarmodule is alwaysoperatedat thepointof maximumpossiblepower. The point of
maximumpowercanvarydependingon theoperatingmode, localconditions, and becauseit
changesin thecourseof theday.
Operating the controller
The display shows avariety of system data by symbols and digits. The buttons on the front panel control
all settings and display windows.
Display and operation elements LCD for controller
information and
messages.
Pagedown button
Manual load switch, or
confirmation button in program mode
(Enter button)
Pageup button
Button for switching display
windows or calling up
the settings (Menu
button)
USB Interfaces
Temperature
Sensor

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Display window
You can change the display windows with the “Menu” button, which provides the following windows:
Default window -> Charge current display -> Load current display -> System clock -> Bulk charge
voltage -> Float charge voltage -> Night light function (NLF) -> Timer1 -> Timer2 -> Default window
Menu Functions and Programming
Default window
The default window will show battery voltage/capacity volume of the
battery, and an overview of the system operation.
Manual load control
At the default display window, press the “enter” button to control the
load ON or OFF. The load icon will turn display to indicate if the load is
turned on or off.
Charge current
Press “menu” button once to check charging current.
(one press from default window)
Load current
Press” menu” button again to display the load current.
(two presses from default window)

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When the charging current or load current is less than 0.5Amp, the
LCD will always show Min A.
When there is no output for charge current or load current, the
display will show 0Amp.
System clock
From the default display window, press “menu” button 3 times to
show controller’s system clock.
To set the time, at the system clock window press “enter” button
once, the hour will flash. You can adjust the hour via Pageup /
Pagedown button. Press “enter” button one more time to confirm the
setup for ‘Hour’ and switch to ‘Minute’ setup mode. You can adjust
the minute via Pageup/Pagedown button. Once it’s done, press
“enter” button for final confirmation.
Bulk charge voltage
Press “menu” button 4times from the default window. Window will
switch to BULK voltage programmable setup interface. Press
“enter” button once, you can program charge voltage via the
Pageup/Pagedown button:
12V Battery(13.8V-14.8V); 24V Battery(27.6V-29.6V)
Float charge voltage
Press “menu” button 5times from the default window. Window will
switch to FLOAT voltage programmable setup interface. Press
“enter” button once, you can program charge voltage.via
Pageup/Pagedown button:
12V Battery(13.0V-14.2V); 24V Battery(26.0V-28.4V)
NOTE: When programming the FLOAT voltage, if you press the
Pagedown button to go below 13.0V, the LCD will display OFF;
meaning that the float voltage is set to ambient temperature
control.

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Night mode
If solar array can not provide current or the current is less than 1 Amp
for 5minutes or more, the controller will switch to Night mode.
Night light function
Press “menu” button 6times from the default window. Window will
switch to NLF setup interface. Press “enter” button once, then
using Pageup/Pagedown buttons, choose “ON” or ”OFF” and then
confirm with the “enter” button.
Timer 1, NLF=ON
With the NLF switched to ON, press “menu” button once from the
NLF window, and the window will switch to Timer1 setup interface.
Press “enter” button once, you can adjust the “Hour”(1-12hours)
via “Pageup/Pagedown” button, and then confirm by “enter”.
Timer 2, NLF=OFF
Press”menu” button again from Time1, window will switch to
Timer2 setup interface. Press “enter” button once, you can adjust
the “Hour”(1-12hours) via “Pageup/Pagedown” button, and then
confirm by”enter”.
NOTE
Timer1 hour setting controls the time the load is turned ON after entering night mode; Timer2 hour setting
controls the time the load is turned OFF after Timer1 has finished. Once Timer2 is finished, the load will
turn ON automatically untill dawn.(See below diagram)
There are 2 modes of night light load control available: Standard Controller Mode and
Evening/Morning Mode. To program standard controller mode, set NLF=OFF.
The MP-3735 recognizes days and night based on the solar array voltage. NLF will start when the
PV(Voltage) < 10V for a period of time.

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Standard Timer1 &Timer2 setup, with NLF=OFF
If you set NLF=OFF, then you can program the standard load control
functionality with Timer1 and Timer2. Press “menu” button 6times
from the default window, taking you to NLF setup interface. Press
“enter” button once, choose NFL OFF via ‘Pageup/Pagedown’ button,
and then confirm by “enter”.
Press “menu” button once from NLF window, Window will switch to
Timer1 setup interface. Press “enter” button once, you can adjust
‘Hour’ via ‘Pageup/Pagedown’ button. After ‘Hour’ setup press ‘enter’
button for confirmation and switch to ‘Minute’ adjustment. You can use
‘Pageup/Pagedown’ button to adjust it. This can be confirmed by
pressing ‘enter’ button. Through ‘Pageup/Pagedown’ button, choose
‘ON’ or ‘OFF’ or ‘ON/OFF’ and then confirm by ‘enter’ button.
Press ‘menu’ button again,window will switch to Timer2 setup interface. Similar operation for time and
ON/OFF setup as mentioned above.
NOTE for programming Timer1 & Timer2
Setting either Timer to ON sets the time when you want to turn the load on.
Setting either Timer to OFF sets the time when you want to turn the load off.
Setting either Timer to “ON/OFF” will disable the timer, and the load output will revert to manual load
control.
Functional Explanations
1. PWM Charge control
Depending on the actual battery level, various charging procedures, float charging, boost charging
and equalization charging are automatically performed. The final charging voltage is temperature
compensated.
2. Deep discharging protection
If the battery falls below aspecified charge level or battery voltage, the load output is disconnected
and the discharge of the battery is prevented. The set points of the deep discharging protection are
predefined and cannot be reset.
3. MPPT function
MP-3735 uses the latest MPPT technology at all times which gives the maximum available output of
the solar module.
4. 5V USB output
Provide 5Vdc/500mA power supplier.
5. 2timers, control the load output automatically.

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6. Temperature Compensation
The charge voltage changes with battery temperature.
Temperature compensation of charge voltage leads to
increase battery life and decrease battery maintenance. MP-
3735 is supplied with a 3 meter temperature sensor cable for
the provided external battery temperature sensor. Charge
voltage will continuously adjust to the proper value based on
actual battery temperature, which ensures that the battery
receives the proper charge voltage as battery temperature changes during the normal operation.
MP-3735 has both internal and external temperature sensor to detect the ambient temperature. The
controller defaults to use internal temperature sensor if external temperature sensor cable is not
connected. Once the external temperature sensor cable is connected, the controller will automatically
switch to the external temperature sensor.
The graph below shows how the MP-3735 would use the external temperature sensor to adjust the Float
Voltage based on the ambient temperature.
Installation
Danger of explosion from sparking! Danger of electric shock!
Only install the controller near the battery on asuitable surface. This surface should be solid,
stabile, even, dry and nonflammable.
The battery cable should be as short as possible (1-2m) and have asuitable cable diameter size for
minimum loss.(Recommended cable for MP-3735 is 25 sq.mm and 2mlength)
Do not install MP-3735 outdoors, the unit should be installed so that it is protected against
humidity, dripping, rainwater as well as direct and indirect warming from sunlight.
To ensure proper air circulation for cooling MP-3735, an area of 15cm on each side of the MP-3735
must be kept free.
The LCD display should be protected against UV rays(e.g. sunlight). Long time exposure to UV
rays can permanently discolor the LCD
The solar charge controller may onlybe connected to the local loads and the battery by qualified
personnel and in accordance with the applicable regulations.
Follow the installation and operating instructions for all components of the PV system.
Ensure that no cables are damaged.
Ensure that polarity of Solar panel/battery/load is connected in proper way.
Ensure all terminations are secure and clean.

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Warning
The controller may only be connected to the local loads and the battery by trained personnel and in
accordance with the applicable standards and regulations.
Ensure that no cables are damaged.
At avoltage of 65V, particularly with regard to module open circuit voltage, the entire solar energy system
must be installed with protection class II. Cover solar modules during installation
Use only insulated tools.
1. Mounting the solar charge controller
1.1 Do not mount the solar charge controller outdoors or in wet rooms
1.2 Do not subject the solar charge controller to direct sunshine or other source of heat.
1.3 Protect the solar charge controller from dirt and moisture.
1.4 Maintain aminimum clearance of 15cm below and around the device to ensure unhindered
air circulation
1.5 Mount the solar controller as close as possible to the batteries (with asafety clearance of at least
35cm).
2. Fix the solar charge controller
2.1 Mark the position of controller fix holes on the walls;
2.2 Drill 4pcs Ø6mm holes and insert dowels.
2.3 Fix the controller to the wall with the cable openings facing downwards, using 4oval head
screws M4x35 (DIN 7996).
Grounding
Grounding MP-3735 is not technically required when installing astand alone solarsystem. However, if
required, common grounding of the negative of the PV array, battery and load control output is OK
for negative earth electrical systems (such as a caravan or motor-home).
Caution: MP-3735 can ground the negative only.
Install the solar system and operating mode
Connect the wires in the sequence from 1to 6according the above diagram.
Disconnect the wires in the REVERSE sequence from 6to 1according the above diagram.
Use with 12V or 24V batteries, controller will detect voltage of battery automatically.
Never exceed thenominal ratings for solar panel array: 360 Watts with 12 Volt battery/ 720
Watts with 24 Volt battery (see below technical data for reference).
Suggested cable length, 10m solar panel connection cable/2m battery connection cable/5m load
connection cable

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TECHNICAL INFORMATION
Max PV Array Size 360W-12V battery, 720W-24V battery
PV Array Voltage
12V or 24V nominal only
Max. Input Current 30Adc
Max. Input Open Circuit Voltage (OCV) 65Vdc
Max. Load Current 30A dc
Charge Voltage(Bulk) 13.8V-14.8V/27.6V-29.6V
Charge Voltage(Float) 13.0V-14.2V/26.0V-28.4V
Deep Discharge Protection Voltage 11.0/22.0V dc ±2%
Output Voltage 12/24V dc
Typical Idle Consumption <50mA dc
Operating temperature -20°C/+50°C
Charging Curve
Bulk Absorption Float Bulk: This is the first stage where the battery is in a
low charge state, where it receives the majority of its
charge. During this stage the battery brought to
about 85-95% capacity getting 100% of the
available solar power.
Absorption: In this stage the controller charge at a constant voltage and the battery is allowed to
absorb current at a constant voltage. The constant voltage regulation prevents overheating and
battery gassing; this stage terminates when the battery current is below 3 Amp or after 3 hours
entered in absorption mode.
Float (Maintenance):After the battery is fully charged, the controller reduces the battery voltage to
a float charge, providing minimal current.
Protection functions
Overcharge protection
Deep discharge protection
Battery under-voltage protection
Solar panel reverse current protection
The following faults will not destroy thecontroller. After correcting the fault, the device will continue
to operate normally:
Overcharge protection
Deep discharge protection
Reverse polarity protection of load, panel and battery
Automatic electronic fuse
Short circuit protection of load and panel
Over voltage protection for solar panel input and battery voltage
Open circuit protection without battery
Reverse current protection at night
Overload protection