Atkinson Electronics SUNEXPLORER III Series User manual

35Amp Solar MPT/PWM
Charge Controller and Display
Part#SEDCM
SUNEXPLORER III™
Manufactured by: Atkinson Electronics, Inc.

www.atkinsonelectronics.com Circuit Board Division
800.261.3602 Revised 07/18
Table of Contents
Diagrams................................................................................................................. 1
Description ............................................................................................................ 2
Specifications....................................................................................................... 3
Description of Operation .............................................................................. 4
Charging Graph & Stage Description ..................................................... 5
Wiring Diagram................................................................................................... 6
Choosing a Mounting Location.................................................................. 7
Installation Instructions................................................................................. 8
Battery Type, Temperature Scale & Set Up Instructions........... 9
Mounting Instructions................................................................................. 10
Power Up Initializations Routine........................................................... 11
LED Indication................................................................................................... 12
User Select Button Installations............................................................. 13
Trouble Shooting Tips.................................................................................. 14
Fault Indications & Cleaning Tips.......................................................... 13
Appendix A ......................................................................................................... 16
Appendix B.......................................................................................................... 17
Limited Warranty............................................................................................ 18
Appendix C.......................................................................................................... 19

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Diagrams
FRONT SIDE
BACK SIDE
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Description
FRONT SIDE OF CONTROLLER
4 MOUNTING BRACKET SCREWS: Bracket clamps the wall paneling between faceplate
and brackets, NO screws to come loose.
BACKLIT LCD DISPLAY: 3 DIGITS 0.50” tall for easy reading.
LED SELECTION INDICAT ORS: Lit red & green LED indicates which position is selected.
BATTERY/SOLAR STATUS READING:
Battery: Voltage, battery & temperature.
Solar: Panel voltage, charge Amps & Amp hours.
Charge Status: Top off.
SELECT BUTTON: Allows user to scroll thru LED positions.
CHARGE STATUS/ TOP-OFF POSITION:
Charge Status LED color indicates following:
OFF: Night mode - Solar voltage insufficient to charge battery(s).
GREEN: Controller is in the float stage of the four stage charge routine.
RED: Controller is in the bulk/absorption stage of the charge routine.
BLINKING GREEN: Controller is in the auto bulk/absorption stage as a result of
battery voltage dropping below 13.0V while in float stage for 5 minutes.
ORANGE: Equalization Charge.
BACK SIDE OF CONTROLLER
DISPLAYS MICRO PROCESSOR: Microprocessor controls all displays and read-out
functions.
4 MOUNTING BRACKET SCREWS: Bracket clamps the wall paneling between face plate
and brackets, no screw to come loose.
MOUNTING OPENING SIZE:
Minimum opening size is 4.10” x 3.40” +/-0.10”
Maximum opening size is 4.20” x 3.45” +/-0.10”
BATTERY/SOLAR PANEL CONNECTIONS: 4 hex screw lugs that will accept a 6-12 Awg
wire. (Batt + Solar + Solar –and Batt-). Torque and Hex screws to 16 inch pounds
(1.8N.m) recommend using NoAlox on Battery & Solar connections to avoid oxidation
problem due to moisture.
BATTERY TEMPERATURE SENSOR CONNECTORS: Input has two functions:
When the controller is powered with the shorting shunt on the sensor connector, the
SunExplorer III allows the installer/ user to select the battery type, when the shunt is
removed the controller stores the battery type selected.
When a LM335T-x sensor is mounted in the battery box and connected to the controller, the
charge rate is adjusted based on temperature of the battery.
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Specifications
Size & Weight: 4.0” H x 4.70” W x 0.75” D, 5.9 ounces
Mounting: 3.5” H x 4.15” W cutout opening with mounting
brackets
Power: 9 to 16 DC from battery
Maximum Charging
Current (Amps): 35 Amps from solar panel array (620 watts max.)
Maximum Charging
Solar Voltage: 25VDC (open circuit voltage) from solar panel array
Bulk/Absorption 14.4VDC / 14.4V/ 14.0V
Voltage: Wet Lead-Acid/ AGM/ Sealed/Gel
Float Voltage: 13.7V (Wet Lead-Acid/ AGM/ Sealed/ Gel)
SunExplorer’s Idle 15mA normal mode
Current Draw: 35mA with back light on
Display: 3 digit LCD to 999 or 99.9 with
decimal 0.5”character height
Battery Percent 12.8V = 100%, 12.55V = 75%, 12.4V = 50%
Remaining: 11.75V = 25%, 10.5V = 0%
Low Battery: Detects low battery @ 11.8V
Battery Type: Wet, AGM, Sealed/ Gel (default is wet battery)
Temp Sensors: LM335T PT (Required for temperature compensation)
Available in 96” or 192” wire lengths
Temperature
Compensation: 24mV/°C .13mV/°F
Solar Voltage: Display range 0 to 25.0VDC
Solar Charge: Display range 0 to 35.0 Amps
Solar Amp Hours: Display 0 to 999 accumulated
Solar Charge 7th LED position not lit –not charging –night mode
Status: Red LED: Bulk charging stage
Green LED: Floating charging stage
Orange LED: Equalization charging stage
Temperature: -10 to 55°C/ -14 to 131° F
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Description of Operation
The SunExplorer III is a six (6) stage, micro-processor based, Pulse Width Modulated (PWM), and
Multi-Point Tracking (MPT), solar charge controller. The controller connects between the solar
panels and 12VDC storage batteries to regulate charge. The SunExplorer III controller maintains
maximum charging rates throughout each of the charging stages, maintains battery life by
protecting it from over charging or under charging by regulating the PWM rates, and disconnects
the batteries at night to prevent discharge thru the solar panels. The SunExplorer III provides an
automatic equalization stage for lead-acid (wet) batteries that are drained down to 12VDC.
The SunExplorer III monitors both the battery and solar panel voltages and determines when and
how to charge the battery. Each morning, when solar panels produce a voltage greater than
10VDC the display portion of the controller wakes up and checks for a low battery/ equalization
flag and the current battery voltage to determine which charging stage to enter, soft charge
(Batteries less than 10VDC) or bulk charge. When the solar panel voltage reaches 16.0VDC the
controller enters the bulk charging stage, charging the battery up to the bulk charge voltage. The
SunExplorer III then enters the absorption stage and begins modulating its charging PWM
algorithm to maintain the bulk charge voltage. The absorption period is based on the battery
voltage before it started charging. Once it completes the absorption phase it then drops into the
float stage, maintaining the battery voltage at 13.7V by adjusting its PWM algorithm to
compensate for varying solar (sunny/cloudy) and DC load conditions to maintain float voltage. If
solar or load conditions are such that the battery voltage is pulled below 13.0VDC for more than
10 minutes an auto boost flag is set and when the conditions improve and the battery voltage
returns to the float voltage the controller sees the boost flag and performs the auto boost routine
then returns to the float stage. When the solar panels output drops below 10.0 volts the
SunExplorer III enters its night or end of day mode.
The SunExplorer III performs the following functions:
1. Monitors both battery and PV voltages to determine when to begin its charge routine each
day and how it is to progress through its charging stages.
2. Monitors the battery temperature sensor and compensates for rising or falling battery
temperatures (requires battery temperature sensor AEI-LM335t).
3. Monitors for low battery voltage, when detected it will blink the battery voltage LED and
display the battery voltage.
4. Compensates for varying solar (sunny/cloudy) and DC loads conditions by adjusting it,
PWM charging algorithms to maintain an optimum float charge.
5. Auto boost feature will occur when the controller cannot maintain float voltage due to
excessive loads and the battery voltage is pulled down below 13VDC. Charge Status LED
Indicates which stage the controller is in: Red - Bulk and Absorption, Green - Float, Orange
- Equalization, Blinking Green - nearing end of day, Charge Status LED OFF –Night
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Charging Graph & Stage Description
Stage 1 –Soft Charge
When the batteries are discharged below 10VDC, the controller will softly ramp the battery
voltage up to 10VDC before applying the full bulk.
Stage 2 –Bulk Charge
Maximum charge current from solar panels until the batteries rise to the absorption voltage.
Stage 3 –Absorption Charge
Battery voltage is maintained at a constant voltage using PWM technology to finish charging the
batteries to a 100% of charge.
Stage 4 –Battery Equalization Charge
Battery Equalization is only available for (WET) flooded led acid battery. When the battery voltage
has dropped below 12.0VDC the controller will automatically run the equalization stage to bring
the internal cells of the batteries to an equal state and reverse the loss of capacity to being
discharged below 12.0VDC once every 28 days.
Stage 5 –Float Charge
The Batteries are fully charged at this point and are maintained at a safe voltage level. During the
float charge the controller is constantly adjusting its PWM control to adjust for varying solar
charging currents and trailer loads to maintain a float voltage of 13.7VDC.
Stage 6 –Automatic Boost Charge
When the controller is in float charge and the trailer loads are greater than the solar charging
current and the battery voltage is pulled below 13VDC, the controller will set an auto boost flag
and when loads are reduced, it will perform a bulk/absorption charge restoring the batteries to
100% and then return to the float charge.
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Wiring Diagram
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Choosing a Mounting Location
Most trailer manufacturers have a recommended location that provides easy accessibility for
running wires from the charge controller to the batteries and solar panels mounted on the roof.
The SunExplorer III-35 should be mounted:
As close to the batteries as Feasibly possible, avoid long wire runs
>10 feet, longer runs have higher voltage drops when charging.
Where there is sufficient depth behind the controller (min. depth 1 1/4")
To allow for the battery and solar panel wires and ventilation.
Away from moisture and heat sources (sinks, shower, stoves etc.).
The controller needs to be protected from steam, water and spray cleaners that can get
behind the faceplate, causing damage to the unit.
Indoors away from doors and windows, protected from weather.
WARNINGS –IMPORTANT
This charge controller is designed for indoor use only and should never be exposed to moisture
(water or rain). It will damage the electronics.
Electricity can be very dangerous. Installation should be performed only by a licensed
electrician or qualified RV service technician.
When working around batteries, always wear protective eye wear and appropriate clothing,
observe all safety precautions of the battery manufacturer. When batteries are charging, they
produce hydrogen gas which is highly explosive. Avoid any sparks or open flame when
charging.
Always cover the solar panels with a thick cloth or blanket to block out ALL light before
connecting the panel wiring to the charge controller. Avoid accidental shorting of the wires
or terminals which could cause personal injury or damage to the unit or sparks causing a fire.
Disconnect all power sources before installation (utility power & batteries)
Observe correct polarity when installing. Reverse polarity of either the solar panel or battery
connections could cause damage to the controller.
Ensure all electrical connections are tight and secure. Torque hex screws to 16 inch
pounds, re-torque after ten days of operation to avoid any loose connections that can
cause sparks and/or excessive heat.
Do not exceed the SunExplorer III-35’s Maximum current (Amps) and PV voltage ratings, total
of 35 Amps (IMP) and 25.0VDC (VMP). See solar panels electrical ratings info tag found on the
back side of the solar panel.
Tools and Materials needed for Installation
Philips Screwdriver (for mounting bracket screws)
Torque Allen Wrench (for wire terminals)
Wire stripers or utility knife
Small hole saw or utility knife (for cutting opening for flush mounting) 7

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Installation Instructions
1. Complete the installation of the solar panels. Follow the solar panel manufacturer’s
instructions for solar panel mounting and wiring to a weather proof multi panel junction box.
Cover panels with an opaque material (several layers of a thick blanket) until wiring is
complete.
2. Prepare the site for mounting the controller. Use the cut-out template found in Appendix C
to mark the outline of the 4.15" x 3.5"opening for flush mounting of the controller.
3. Select wire type and gauge. (See Appendix B) It is recommended that stranded copper UV
resistance wire be used. Wire fatigue and the possibility of a loose connection are greatly
reduced by using stranded wire over solid wire. The wire gauge must be able to sustain the
rated current (3.5 Amps) as well as minimizing voltage drop. Keeping the distance between
PV junction box, the charge controller and batteries, as short as possible, this will minimize
the voltage drop.
Suggested minimum wire gauge and fuse size:
300 Watts of Solar Panels # 10 Gauge Wire 25 Amp Fuse
450 Watts of Solar Panels # 8 Gauge Wire 35 Amp Fuse
600 Watts of Solar Panels # 6 Gauge Wire 40 Amp Fuse
(25ft. Maximum Cable Length from solar panels to battery bank.)
4. If possible use red and black cables or mark both ends of each cable with colored tape to
indicate which cable is positive and negative, to avoid possibly hooking the cables up
backwards and damaging the controller.
5. Run the wires from the solar panels and the batteries to the location of where the SunExplorer
III controller will be mounted. If a battery temperature sensor is to be used, run it with the
set of cable coming from the battery compartment. It is also required that an in-line fuse be
installed at the battery location to protect both batteries and controller (for ease of
accessibility, see Appendix A). If a wire ever came loose and caused a short, you do not need
continuous arcing to cause a fire. Do not connect the wires to battery at this time.
6. The SunExplorer III has four terminals marked as follows: BAT(+), PV(+), BAT(-) , and PV(-).
Strip the insulation back 3/8" (9.5mm), insert each wire into the correct terminal, tighten
enough to hold the wire, reverify polarity, and then tighten each connection to 16 inch pounds
(1.8N.m).
7. Do not connect temperature sensor to the controller at this time. At battery location,
remove fuse from the fuse holder or open the resettable breaker, then finish connecting the
in-line fuse to the controller’s battery + wire, and connect the other end to the battery + (pos)
terminal. Connect the controller’s battery neg (-) wire to the battery neg (-) terminal.
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Battery Type & Temperature Scale Set Up
At this point in the installation you need to select your battery type and the temperature reading
to be displayed in either °F or °C.
1. Check to make sure the shorting jumper is on the temperature sensor connector. Then insert
the recommended fuse (amperage based on total solar panel wattage) into fuse holder. This
powers the charge controller. The SunExplorer III controller will power up displaying “888"
for 3 seconds then it will enter setup mode, displaying the battery type and temperature. The
battery/temp LED will be illuminate.
2. The display read out will show “FLF”, the factory default setting if being powered for the first
time. FL = (WET) Flooded lead acid battery type and F= Fahrenheit temperature scale. If this
is correct go to step 7.
3. If the display doesn’t match your system, press and hold the select button for 5 seconds, the
left two characters will flash and rotate through the 3 battery types: FL=(Wet) Flooded cell,
GL = Gel Cell and AG = AGM cell. It will show each for 5 seconds.
4. When the display is showing correct battery type press and hold the select button for 5
seconds, this stores the battery type, the left two characters stop flashing and the right
character will begin flashing and alternate between the two temperature scales, F=Fahrenheit
and C=Celsius.
5. When it shows the temperature scale you want, press and hold the select button for 5 seconds,
this stores the temperature type and stop flashing the display and battery type/Temperature
LED.
6. If not satisfied with your selection, repeat steps 3 through 5.
7. If you’re satisfied with the battery type and temperature scale, remove shorting jumper from
the temperature sensor input pins and attach it to this manual, you will need it if you change
your battery type in the future. The SunExplorer III exits the setup mode.
8. If you installed to optional battery temperature sensor, connect it to the temperature sensor
terminal. The Display now indicates battery temperature.
9. If you didn’t install the optional temperature sensor the display indicates the battery type and
temperature scale you selected.
10.Remove fuse from the in-line battery fuse holder to power down the controller. Now it is time
to complete the mounting instructions.
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Mounting Instructions
1. Using a Phillip screw driver loosen the four mounting bracket screws until they reach the stops.
Angle the screws and brackets inward as shown below.
2. Carefully work the wiring into the wall, and insert the mounting bracket into the opening,
adjust the face plate to be parallel to the wall surface.
3. Center the controller in the opening against the wall, using a Philips screw driver, tighten each
screw 10 to 14 full turns. This brings the mounting clip evenly toward the wall and face plate.
4. Adjust each screw until it comes in contact with the wall. Readjust the face plate if needed to
align or center it in the opening. Now tighten all four screws, so that the plate is secure against
the wall. DO NOT over tighten the screws.
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Power Up Initialization Routine
Now that the installation of the SunExplorer III controller is complete, re-insert the fuse into the
battery fuse holder to power the controller. If Powering up for the first time after installation or
after replacing a battery, the SunExplorer III runs thru the following sequence: PV panels are still
covered from installation process.
1. When first powered the SunExplorer III display will indicate 88.8 and back light will turn on.
The display will indicate the following, each for 3 seconds,:
The software revision................. “1.2"
The rated system voltage….........“12"
The rated maximum current......“35"
2. The controller will then cycle thru the seven display positions, lighting the corresponding
LEDs, displaying eleven readings, each for 3 seconds.
Battery % remaining …….......... “100" % (Actual reading)
Battery voltage.............................. “12.9" V (Actual reading)
Battery type / Temperature
“FL.F” (Flooded Battery……...Fahrenheit temperature scale)
“GL.C” (Gel Battery................... Celsius temperature scale)
“AG.F” (AGM Battery………..... Fahrenheit temperature scale)
Battery Temperature “77”F (Displays actual temperature, if temperature sensor is
connected)
Solar Voltage “LPu” (Low PV voltage, panels are still covered or its night time)
(example “19.5" V, if panels are uncovered and its day time)
Solar Charge Amps........................“0.0" (Still in night mode)
(example “25.0" Amp, if panels are uncovered)
Solar Charge Amp Hours “ 0.0" (unit has begun to charge)
LED Charge Status:
LED GREEN night mode.........................“n_c”
Blinks RED bulk charge.........................“bch”
Blinks RED absorption charge……....“Ach”
Blinks GREEN float charge..................“Fch”
Blinks GREEN auto boost enabled...“AbE”
Blinks ORANGE Equalization.............“Ech”
Blinks RED Soft charge.........................“Sch”
Once the controller has run thru the power up sequence, the controller will return to normal
mode, returning to battery % remaining position, displaying the charge of the battery, and will
blink the LED once every 10 seconds, indicating it in night mode (solar panels are still covered).
Now remove the blanket or material covering the solar panels. If the panel voltage is greater than
16.0VDC the charge controller will enter the bulk charge stage, causing the charge status LED to
lite red and blink if in soft charge or be solid for bulk charge. The back light will be lit for 30 seconds
and then turn off and the battery % remaining reading will still be indicated on the LCD display.
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LED Indication
The SunExplorer III controller has seven LEDs, six that only illuminate green, and one LED that
can illuminate red, green, & orange depending on the charge stage it is in. Each LED and text
correspond to what is being indicated on the LCD display screen.
LCD displays:
0 to 100%
8 to 16.0 VDC
One of: FL, AG, GL / °F or °C then 77'
0 to 25.0VDC
Charge <1 Amp, 1 to 40.0 Amps
0.0 to 999
One of 7 charging conditions.
(n_c, Sch, Bch, Ach, Ech, Fch, AbE
When the controller goes into night mode, the battery % remaining LED will blink once every 10
seconds. When morning arrives and the solar panel voltage rises above 10VDC the LED will stop
blinking even though the controller has not gone into bulk charge mode. When the solar panel
voltage increases to 16VDC it will enter the bulk charge stage lighting the charge status LED red.
When the battery has charged to the bulk/absorption voltage threshold the controller enters the
absorption charge stage, charge status LED remains red. If you scroll down to the charge status
position the LED will blink red and LCD displays ‘Ach’. Once the absorption time has been satisfied
the controller enters the Float stage.
If the controller is in the float stage of charge and the charge status LED is blinking, it indicates
that the controller’s PWM rate is at 100% and unable to maintain a 13.7VDC float voltage. This
could be caused by either or both, solar panels not providing a high enough charge voltage or the
trailer battery loads are greater than what the solar panels can supply, thus the battery voltage
has dropped below 13.0VDC. When the condition is resolved the controller’s status LED is solid.
It will then check the PV voltage and if greater than 16V, it will perform an auto boost charge (bulk
charge with a 30 minute absorption charge period) then returns to a float charge state.
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User Select Button Instructions
1. The SunExplorer III’s display will normally revert back to displaying the continuous battery
percent remaining after approximately 4 minutes from any other reading.
2. Select button operation:
a. Pressing the select button activates the back light for 15 seconds.
b. Pressing the select button to advance, also resets the 15 second timer.
c. Pressing for 1-2 seconds then release the button, advances to the next reading.
d. From the battery % remaining position only, pressing and holding the button will advance
the display automatically through each of the readings.
i. If the button is released before returning to the battery voltage display, the reading
will remain in that position until the display times out (4 min.)
ii. If the button is held through all readings and then released after the battery voltage
display, the SunExplorer III will enter the scroll mode, advancing to the next reading
every 3 seconds, indefinitely.
iii. Tapping the button exits the scroll mode.
iv. A low battery voltage condition will also exit the scroll mode.
e. Display lock mode is available for: Battery voltage, battery temperature, solar panel
voltage, solar charge Amps.
i. To lock display from timing out and reverting to battery % remaining, advance display
to desired position then press and hold the button until the display flashes
(approximately 3 seconds).
ii. Release the button when the display starts flashing, it will remain indefinitely in that
reading or until the select button is pressed again.
iii. Advancing to the next reading cancels the lock mode.
iv. Low battery voltage also cancels the lock mode.
f. Resetting the solar accumulated Amp hour reading zero.
i. Pressing and holding the button for approximately 6 seconds will reset the display value.
The display starts flashing after 3 seconds, the reading goes to zero after 6 seconds and
the display stops flashing.
ii. Releasing the button while the display is flashing cancels the reset. It will stop flashing
and retain its current value after several seconds.
g. Manual boost/ battery top off is available only when controller is in float charge stage.
Advance to charging status, display will indicate “Fch”.
i. Press and hold the select button the display will flash “Fch” 4 times, telling the charge
controller to enter the charge routine. When controller enters charge mode the green
status LED turns RED and the display indicates “bch”, 3 second later display jumps to
solar charge Amps and shows the charging current for 10 seconds, then to battery
voltage showing the battery voltage, then it alternates between them until it exits the
charge routine or the select button is pressed.
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Trouble Shooting Tips
Problem: The SunExplorer III display is blank and there are no LEDs lit.
Solution: Check the Fuse in the Battery (positive) wire at the battery to see if it has blown.
Recommend using a multi meter to Ohm the fuse. If the fuse is good then check the battery
voltage at the battery and at the Controllers battery + terminal, they should be the same, above
8.0VDC. If the battery voltage is below 7.5VDC the controller will not function. Make sure the
polarity is correct as positive to positive. If there is no voltage reading at the controller battery
terminals, the problem is in the wiring between the battery and the controller. Check ALL
connections from the controller to the battery terminals. Check that ALL connections are clean,
tight and secure. If you haven’t greased the connections, it is Recommended that all power
connections between solar panels to controller to batteries be greased with NoALOX 0.5oz.
Problem: The SunExplorer III controller is always in night mode, even though it is a bright
sunny day. Green LED blinks once every 10 seconds.
Solution: Using the SunExplorer III’s display scroll down to Solar panel voltage, if the solar
panel voltage is less than the minimum required voltage to charge the batteries it will display
“Lpu” low panel voltage.
Check to see if something is covering or blocking the sun light from reaching the solar panels.
Check to make sure the panels are not too dirty to supply a high enough voltage for the controller
to go into charge mode. If you fused the positive wire from the solar panels, check to see that the
fuse is good. If the fuse is good, then measure the solar voltage at the controller PV terminals, it
should be greater than 16.0VDC. If you don’t have a voltage present, then check each solar panel
to make sure they are producing a voltage. If you have multiple panels disconnect one at a time
and measure its output voltage, it only takes one shorted solar panel to bring the whole system
down.
Problem: The SunExplorer III’s battery voltage reading is different from what I’m reading with
my multi meter.
Solution: The SunExplorer III’s reads both the battery voltage and solar panel voltage every
second to know the true battery voltage (without being pulled up while being charged, and the
open solar collector voltage to know what the voltage the panels are producing to know when to
charge or shut down for the night. Battery voltage should be within 0.2VDC of the battery voltage
when not charging.
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Fault Indication
Fault 1 –Low battery voltage. The SunExplorer III display has advanced to the battery
voltage location and blinks both LED and display reading. This occurs when the battery voltage
has dropped to 11.8VDC, a level that could start to damage your batteries. This generally occurs
at night when the SunExplorer III cannot charge the batteries. Recommend turning off all loads,
plug into shore power or use a generator to charge the batteries.
Fault 2 –Battery high temperature.The SunExplorer III display advances to battery
temperature location and blinks both LED and battery temperature and the SunExplorer III backs
off the charging current to prevent further heating of the batteries. Once the battery temperature
drops below 125 degrees F, the SunExplorer III will regulate the charge to keep the battery(s)
temperature from increasing. Once the temperature has dropped enough to resume normal
PWM charge rate the display will stop flashing.
Cleaning Tips & Warnings
Do not spray water or cleaning solution directly on the face plate or LCD of the SunExplorer III-35.
The liquid could run between the face plate and the LCD on to the circuitry of the SunExplorer III-
35 circuit board causing damage to the electronics and WILL VOID THE WARRANTY!
Recommendation for cleaning SunExplorer III: Apply water or cleaning solution to a soft cloth and
spot clean the face plate as needed.
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Appendix A
Recommended grease for all power connections between photo-voltaic
panels, SunExplorer’s charge controller and battery bank.
Brand: IDEAL No ALOX 0.5oz
Available at most hardware stores.

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When selecting the correct amperage rating for your in-line circuit breaker, first determine the
maximum current output of your solar panel array by adding up the current at maximum Power
(Imp) for each panel, then round up to the next standard amperage size.
Example: (3) 150watt panels, Imp = 8.5Amps ea. Total Imp. = 25.4Amps
Recommended fuse or circuit breaker size 30 Amps.
In-line Fuse examples (Resettable or Blade type)
Bussman Maxi in-line fuse holder
Part number: HHX (6 Awg wire)
Bussman Maxi Fuse
Available in 20, 25, 30, 35, 40 & 50 Amps
Part number: CB185-XX
XX= Amp rating
Bussman Resettable Circuit Breaker
Available in 20, 25, 30, 35, 40 & 50 Amps
XX=AMP rating
Automotive Audio Resettable Breaker
Available in 20, 30, 40 & 50 Amps
The fuse, fuse holder and circuit breakers are available at any of the major on-line retailers.
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Appendix B
Amp Verses Wire Gauge Chart

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800.261.3602 Revised 07/18
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