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COMMUNITY ENERGY
MALAWI
This manual has been designed to impart technical knowledge to people on
the basic design, operation and maintenance of solar PV systems.
SOLAR PV
TECHNICIANS
TRAINING MANUAL
Contents
GLOSSARY ..................................................................................................................................................... 2
INTRODUCTIONS .......................................................................................................................................... 4
TOPIC 1: SYSTEM INSTALLATION AND PANEL ALLIGNMENT ......................................................... 6
Module Mounting .................................................................................................................................. 6
Array frames and angles ......................................................................................................................... 6
TOPIC 2: SYSTEM CARE AND SECURITY ............................................................................................... 8
2.1 System Care ....................................................................................................................................... 8
2.1.1 Solar Array .................................................................................................................................. 8
2.1.2 Cable Inspection .......................................................................................................................... 9
Battery Inspection and Cleaning ....................................................................................................... 9
Charger Controller ............................................................................................................................ 12
Inverter ............................................................................................................................................... 12
TOPIC 3: SOLAR PV SYSTEMS PERFORMANCE MONITORING ..................................................... 13
Introduction to performance monitoring parameters ...................................................................... 13
Voltage, Current and Charge............................................................................................................... 13
I.
Introduction Energy generation parameters .......................................................................... 15
II.
Battery storage parameters ...................................................................................................... 18
TOPIC 4: TROUBLE-SHOOTING ........................................................................................................... 21
Introduction to troubleshooting and failure types ........................................................................... 21
Failure type 1: if the battery is discharged ..................................................................................... 21
Failure type 2, if the battery is charged but appliances are not working .................................. 22
Failure type 3: the system works but runs out of power............................................................. 23
Ways to Conserve Energy .................................................................................................................... 25
Index ........................................................................................................................................................... 27
List of Suppliers ...................................................................................................................................... 27
Estimated Component Prices ............................................................................................................... 27
Help Line ................................................................................................................................................ 30
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GLOSSARY
Alternating current (AC) — A type of electrical current, the direction of which is reversed
at regular intervals or cycles. In the United States, the standard is 120 reversals or 60 cycles
per second. Electricity transmission networks use AC because voltage can be controlled
with relative ease.
Ampere (amp) — A unit of electrical current or rate of flow of electrons. One volt across
one ohm of resistance causes a current flow of one ampere.
Battery — Two or more electrochemical cells enclosed in a container and electrically
interconnected in an appropriate series/parallel arrangement to provide the required
operating voltage and current levels. Under common usage, the term battery also applies
to a single cell if it constitutes the entire electrochemical storage system.
Battery life — The period during which a cell or battery is capable of operating above a
specified capacity or efficiency performance level. Life may be measured in cycles and/or
years, depending on the type of service for which the cell or battery is intended.
Charge controller — A component of a photovoltaic system that controls the flow of
current to and from the battery to protect it from over-charge and over-discharge. The
charge controller may also indicate the system operational status.
DC-to-DC converter — Electronic circuit to convert direct current voltages (e.g.,
photovoltaic module voltage) into other levels (e.g., load voltage). Can be part of a
maximum power point tracker.
Deep-cycle battery — A battery with large plates that can withstand many discharges to a
low state-of-charge.
Deep discharge — Discharging a battery to 20% or less of its full charge capacity.
Direct current (DC) — A type of electricity transmission and distribution by which electricity
flows in one direction through the conductor, usually relatively low voltage and high
current. To be used for typical 120 volt or 220 volt household appliances, DC must be
converted to alternating current, its opposite.
Direct insolation — Sunlight falling directly upon a collector. Opposite of diffuse insolation.
Discharge — The withdrawal of electrical energy from a battery.
Electric current — The flow of electrical energy (electricity) in a conductor, measured in
amperes.
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Electrolyte — A nonmetallic (liquid or solid) conductor that carries current by the
movement of ions (instead of electrons) with the liberation of matter at the electrodes of
an electrochemical cell.
Maintenance-free battery — A sealed battery to which water cannot be added to maintain
electrolyte level
Photovoltaic(s) (PV) — Pertaining to the direct conversion of light into electricity.
Photovoltaic (PV) array — An interconnected system of PV modules that function as a
single electricity-producing unit. The modules are assembled as a discrete structure, with
common support or mounting. In smaller systems, an array can consist of a single module.
Photovoltaic (PV) cell — The smallest semiconductor element within a PV module to
perform the immediate conversion of light into electrical energy (direct current voltage
and current). Also called a solar cell.
Photovoltaic (PV) module — The smallest environmentally protected, essentially planar
assembly of solar cells and ancillary parts, such as interconnections, terminals, (and
protective devices such as diodes) intended to generate direct current power under
unconcentrated sunlight. The structural (load carrying) member of a module can either be
the top layer (superstrate) or the back layer (substrate).
Photovoltaic (PV) panel — often used interchangeably with PV module (especially in onemodule systems), but more accurately used to refer to a physically connected collection of
modules (i.e., a laminate string of modules used to achieve a required voltage and current).
Photovoltaic (PV) system — A complete set of components for converting sunlight into
electricity by the photovoltaic process, including the array and balance of system
components.
Sulfation — A condition that afflicts unused and discharged batteries; large crystals of lead
sulfate grow on the plate, instead of the usual tiny crystals, making the battery extremely
difficult to recharge.
Tilt angle — The angle at which a photovoltaic array is set to face the sun relative to a
horizontal position. The tilt angle can be set or adjusted to maximize seasonal or annual
energy collection.
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CEM TECHNICIAN CAPACITY BUILIDING TRAINING
TOPICS COVERED
1.
Basic Introduction to solar (PV) home systems
2.
Panel alignment
3.
System security and care
4.
System performance monitoring
5.
Troubleshooting
INTRODUCTIONS
(i)
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Introduce yourself to the members present, Hello, my name is [your name(s)] I /we
work for Community Energy Malawi. CEM is conducting a technician training to
empower and build capacity of this community [location and name of CBO]. By the
end of our training we expect you to fully understand these topics (mention the topics
above). After the training, it is expected of you to take the leading role in doing
maintenances and monitoring of PV systems installed across your community. It will
also be required of every member (technician) in this training to train 2 other technicians
in the period of 2 years. You are to always report the status of CEDP system to the
energy committee. It must be noted that this training is empowering you to do simple
and basic monitoring and maintenances procedures, therefore if the system(s) have
encountered failures or any other thing that will not be covered in the training and that
which you cannot be able to handle please feedback to the energy committee to report
to CEM.
The training will consist of theory and practical session, practical session will involve
doing actual site demonstration. Participants are therefore required to pay full attention
and ask where they feel not to be in the clear. To evaluate your understanding, after
the demonstrations from the training facilitator you will be required to carry out the
same procedures.
ACTIVITIES
• Ask the CBO members present on training to introduce themselves and what are their
expectations from the training
• The whole idea of the first activity is to settle the climate and enable them to feel free and
participate in the training.
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TOPIC 1: SYSTEM INSTALLATION AND PANEL ALLIGNMENT
Module Mounting
Modules can be fixed on the ground, wall or roof with a frame mount, or integrated into
the building fabric.
Array frames and angles
Solar array frames are tilted so that the modules face the sun. In Malawi modules face
north. For this training, a compass direction will be used to determine the true north. In
tropical areas this means the sun will be south of the array for part of the summer but this
does not greatly affect output. Array frames can be fixed, adjustable or tracking. System
designers choose the right frame for their system. Fixed frames are set at the optimum tilt
angle for the system.
Figure 1: Optimum tilt angles for winter and summer in Malawi
Optimum tilt angle is dependent on the type of load and available solar power. As a rule
of thumb, if the main loads are in winter months when solar availability is reduced, tilt
angles should be more vertical (approximately equal to latitude plus 10º) to maximise
exposure to the low winter sun. If major loads are cooling and refrigeration the tilt angle
should be reduced (approximately latitude minus 10º) to maximise output during summer.
Adjustable frames allow the tilt angle to be varied manually throughout the year to
maximise output year round. In practice it has been found that although many people
change the tilt angle of the frame in the first few years of operation, they forget to do this
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as the years progress.If this situation is likely, it is best to fix the array at the optimum angle
which is 25o for Malawi.
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TOPIC 2: SYSTEM CARE AND SECURITY
2.1 System Care
A solar system needs to be properly taken care of in order for it to last for a long period.
If a system is not well taken care of, its life span can drastically be reduced. Every system
component has its own different care procedure, therefore recommended care
procedures are to be followed.
2.1.1 Solar Array
 The solar array (a number of solar panels connected together) which traps energy
from the sunlight is often thought to be maintenance free. However, occasional
maintenance and inspection of the solar array must be performed to ensure the
optimal use and operation of the solar panels. This can be done by keeping the
surface of the module clean from any excess dirt.

To remove the layers of the dust and dirt from the module simply wash with water.
If the array has thick dirt or grime and bird droppings, which are harder to remove,
wash with cold water and rub the panel surface with a sponge.
Safety First
Do not use a metal brush to clean solar panel surface. Detergents should not be used
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Figure 2: The right way to clean panels

A visual inspection of the modules can then be done to check for defects in the
modules such as cracks, chips, de-lamination, fogged glazing, water leaks and
discoloration. If any obvious defects are found, note their location in the system
logbook, so they can be monitored in the future in case further deterioration affects
the modules’ output.
The condition of the array mounting frame should also be noted. Items to observe
should include the array mounting bolts (e.g. bolt rusting) and checks to ensure that
the frame and modules are firmly secured. The junction boxes should also be
checked to ensure that the wires are not chewed by rodents or insects.
2.1.2 Cable Inspection
Check cables running between PV and batteries, should be undamaged, no bear wire
sticking out of junction boxes etc….
Battery Inspection and Cleaning
A visual inspection should be done to assess the general condition of the system’s batteries.
Check for any electrolyte leak, cracks in the batteries, or corrosion at the terminals or
connectors.
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Batteries should be clean, dry and free of electrolyte and corrosion residue. Corrosion at
battery terminals is seen as a white coating around the battery terminals. Cleaning should
be done once monthly.
Figure 3: a representation of corrosion at the battery terminals
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Safety first
Do not smoke or light fire near batteries. Batteries produce hydrogen gas which is highly
flammable.
Before maintenance is carried out, each component of the system should be isolated. This
would involve switching off circuit breakers to and from the battery bank and the solar
panels. Battery cleaning procedures are as follows:
Figure 4: Solar PV Circuit diagram
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
Switch off/disconnect all loads on the system. Turn off or disconnect the solar
charge controller. Then turn off the circuit breaker to and from the battery bank.

Ensure that the caps on the batteries are sealed tight to keep any dirt from
entering the battery. Wipe the top and outside of the battery with a (damp) cloth.
If corrosion is present at the terminals, mix baking soda with fresh water and
apply the solution to the affected area. Stubborn areas should be scrubbed with a
metal brush. After cleaning, rinse the terminals with water. If available, apply
petroleum jelly or grease to the connected terminal to prevent future corrosion.

Maintenance of gel cell and AGM batteries relates only to the battery terminals
and connections. The terminals and posts should be wiped until they are shiny,
and if corroded, clean them properly with Bi-carbonate soda and water. If
available, apply petroleum jelly or grease to the connected terminals.
Charger Controller
 This component can be maintained by minimizing dust accumulation. A dry cloth
should be used to wipe away any accumulated dirt/dust.

A visual inspection should be done to ensure that all the indicators such as LED lights
are working and that the wires leading to and from this device are not loose

Note that the charge controller should indicate that the system is charging when the
sun is up
Inverter
 Ensure that the inverter is on a flat surface

keep the inverter dry

do not allow it to come into contact with rain or moisture

do not place the inverter near heating vents, direct sunlight or other heat sources

keep the inverter well ventilated by keeping it in an open space
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TOPIC 3: SOLAR PV SYSTEMS PERFORMANCE MONITORING
Introduction to performance monitoring parameters
Photovoltaic system's performance parameters are categorized into three subjects: energy
generation (electricity units like Volts and Amperes), supplemental parameters and the
energy storage for systems with batteries attached. To ensure successful monitoring of PV
systems, it is important to familiarize yourself with the normal values for your system, and
note any deviations from that baseline.
Voltage, Current and Charge
Voltage is defined as the amount of potential energy between two points on a circuit.
One point has more charge than another. This difference in charge between the two
points is called voltage. It is measured in volts, which, technically, is the potential energy
difference between two points that will impart one joule of energy per coulomb of
charge that passes through it. Voltage is represented in equations and schematics by the
letter “V”.
When describing voltage, current, and resistance, a common analogy is a water tank. In
this analogy, charge is represented by the water amount, voltage is represented by the
water pressure, and current is represented by the water flow. So for this analogy,
remember:

Water = Charge

Pressure = Voltage

Flow = Current
Consider a water tank at a certain height above the ground. At the bottom of this tank
there is a hose.
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Figure 5: The water-Voltage analogy representation
The pressure at the end of the hose can represent voltage. The water in the tank represents
charge. The more water in the tank, the higher the charge, the more pressure is measured
at the end of the hose.
We can think of this tank as a battery, a place where we store a certain amount of energy
and then release it. If we drain our tank a certain amount, the pressure created at the end
of the hose goes down. We can think of this as decreasing voltage, like when a flashlight
gets dimmer as the batteries run down. There is also a decrease in the amount of water
that will flow through the hose. Less pressure means less water is flowing, which brings us
to current.
It's important to know what to expect from a solar PV system. Panel performance will
degrade slowly, and smoothly, over time, depending on the kind of photovoltaics that are
used, and when they were built. A 0.5 - 2% loss in output per year per year should be
expected. Inverter problems may show up more abruptly and before the photovoltaics
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reach their end of life. Also, physical damage to your panels can instantly affect their
performance too. Variations in weather do make a difference, so if your panel output this
month is 5% lower than the output from the same month last year, that doesn't necessarily
mean there's a problem. It is important to take note of the states of solar PV systems which
are classified in the following states:
1. Off -Either no energy is produced, the solar panels are isolated, there isn’t enough
exposure to the system, or the system is stopped manually.
2. Idle - panels are in contact with sun rays but the DC power they produce is too low.
3. Active - panels generate DC electricity and the inverter produces and supplies AC
power.
4. An error state - current break, under/overvoltage etc.
I.
Introduction Energy generation parameters
The product of current and Voltage is power. DC voltage is only monitored in idle state. The most
important performance parameter of the system is the inverter's current AC power. Energy
generation can be aggregated through hours (hourly production), days (daily production), months,
years etc. For the sake of this training with CBOs, we encourage daily recording of data at peak
hours of the day (midday).
Practical Procedures
1. Find the nameplate voltage (V) and current (A) ratings of your panel (you can usually find
these written on the back of the panel).
2. Check that sunlight conditions are suitable for producing readings on your system. To
obtain the rated output of your panel you will need full, bright sunlight falling directly onto
the panel. Remember, no sun, no power.
3. Make sure you understand how to use the multimeter, and that you are using appropriate
settings for the power you expect to measure.
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Figure 6: Multimeter
4. If you are testing a charge controller you will need to make sure that the battery is NOT
fully charged otherwise it will not be able to accept current. The first two measurements
use the solar panel on its own. When disconnecting the solar panel, regulator and battery,
take care to disconnect the panel from the Charge Controller first, and then disconnect the
regulator from the battery. When reconnecting, connect the regulator to the battery first,
and then connect to the solar panel. This will avoid causing damage to the regulator.
Safety first
Observe polarities (positive or negative) when connecting solar panels and
batteries.
It is recommended that you cover the front of the solar panel if outdoors to
help avoid shocks.
Do not short circuit either the panel or the battery.
5. Disconnect the solar panel completely from the battery and regulator
6. Ensure that the multimeter is set to measure Volts
7. Measure the voltage between the +ve and -ve terminals by connecting the negative contact
from the voltmeter to the negative on the panel and the positive contact on the voltmeter
to the positive on the panel.
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8. Disconnect the solar panel completely from the battery and regulator
9. Angle the solar panel towards the sun.
10. Ensure that the multimeter is set at 10A, at least to start with. You can change the setting
later if required.
11. Measure the current by connecting the +ve lead on the voltmeter to the +ve on the panel
and the -ve from the voltmeter to the -ve on the panel
12. Connect the panel to the regulator and battery.
13. Ensure that the multimeter is set at 10A, at least to start with. You can change the setting
later if required.
14. Disconnect the positive cable between the battery and the regulator
15. Measure the operating current by connecting the +ve from the multimeter to the positive
cable from the regulator, and the -ve from the meter to the positive battery terminal.
16. This measures the current that the panel (and charge controller) are passed to the battery.
If you connect the meter the wrong way round then you will get a negative current
showing.
17. Remember, if the battery is full it may not be accepting current, resulting in a low reading.
18. Measure operating current as described above.
19. Re-connect the solar panel directly to the battery without the regulator.
20. Disconnect the positive cable between the battery and the panel.
21. Measure the operating current by connecting the +ve from the multimeter to the positive
cable from the panel, and the -ve from the meter to the positive battery terminal.
Note:
If you measure current without the regulator, but not with the regulator, then the regulator may
be faulty. If the battery is full it may not be accepting current, resulting in a low reading. Check the
condition of any fuses that might be in the power path. Verify the system wiring is correct and
intact. Ensure that all the connections and terminals for good electrical contact.
Measurement
Outcome
Current measured with charge The
controller (e.g 1A)
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charge
Result/Action
controller
working and taking current
is No action required, repeat the
test in one mont
NO current measured with The charge controller is faulty
Order a new charge controller
charge controller, but current
measured between panels and
batteries
II.
Battery storage parameters
Practical Procedure
1. Inspect the Battery
There are a several things to inspect on a solar PV system which include: a broken terminal,
bulge or bump in the case, crack or rupture of the plastic, excessive leaking, and
discoloration. Broken or loose terminals are dangerous, and can cause a short circuit. If a
short did occur, there would be some indication of burning or melting. When a battery
short circuits, all of the power is unloaded in an instant. That produces a lot of heat, and
sometimes even causes the battery to explode. If the battery is still intact, but there is a
bulge in the case, this is usually a result of being overcharged. Others signs such as physical
openings in the case are often caused by mishandling. Cracks, splits, and holes will not cause
a battery to stop working, but for safety reasons the battery should be labeled unsafe to
use.
With wet-cell (flooded) batteries, water levels have to be maintained.
Sealed Gel Battery
Figure 7: Types of batteries
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Deep Cycle Flooded- Lead Acid Battery
If they are low, usually re-filling them with distilled water will help. Distilled water can be
sourced from Petrol stations and Water Board Taps. If the battery has been dry for a long
time, it can cause a problem. When the plates in the cells are exposed to oxygen, it rapidly
causes sulfation to build up. Sulfation is the number 1 cause of early battery failure.
It occurs when a lead acid battery is deprived of a full charge plus, charging a dry battery
will burn it up. If your battery has plenty of fluid in the cells, but the color is dark, or
brownish, this is also an indication of a bad battery. Even if one cell is brown, it is rendered
useless and therefore the entire battery is, too.
2. Take a Voltage Reading
The voltage of a battery is a good way to determine the state of charge. Here's a handy
table with the breakdown:
State of Charge
Voltage
100%
12.7 - 13.2
75%
12.4
50%
12.2
25%
12.0
Discharged
0 - 11.9
If your battery is reading 0 volts, chances are the battery experienced a short circuit. If the
battery cannot reach higher than 10.5 volts when being charged, then the battery has a
dead cell. If the battery is fully charged (according to the battery charger) but the voltage
is 12.4 or less, the battery is sulfated. Sulfation is the natural byproduct when the battery
discharges. Naturally, re-charging the battery will reverse the sulfation crystals and turn it
back into electrolyte, ready to produce power again. But if a battery sat uncharged, severely
discharged, and/or drained for extended periods of time, the sulfation will increase in size
and harden onto the plates. This covers the surface area of the plates, removing the
chemicals needed to produce power. Sulfation decreases the potential to reach a full charge,
and it self-discharges the battery quicker than normal. Charging a sulfated battery is like
trying to wash your hands while wearing gloves. At this point, charging alone will not
restore the battery to a healthy condition. The majority of replacement battery purchases
occur when the original battery has reached this point.
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3.
Load Test the Battery
A digital voltmeter should be used for this exercise. For any load test to be accurate, the
battery must be fully charged and do not disconnect the battery. Hold the prongs of your
voltmeter to the correct terminals on the battery. Now connect the AC load and watch
what the voltage drops to. It doesn't matter if the load doesn’t turn on, what you're looking
for is a voltage reading.
A healthy 12 volt battery should maintain a range from 9.5 - 10.5 volts under the load for
a good 30 seconds straight. If the battery begins to hold and then steadily drops in voltage,
there is a problem. If the voltage instantly drops to 0 volts, that is also a problem. We call
this the open cell. On a new battery, this can be a result of manufacturing flaws, but it also
may be caused by sulfate crystal buildup. Under the intense heat of the load, one or more
of the weld pieces connecting the cells is coming loose and separating. This will cut the
current, and voltage will drop. When the battery cools off, the pieces will touch, barely
giving a complete connection. This gives you a false voltage reading. Batteries with open
cells may read fully charged in idle, but they fail under a load test every time. Once a
battery reaches this point, there is no going back. The best thing to do is recycle.
Summary
If the performance evaluation shows that the system is underperforming, the following tasks may
be carried out to detect system faults.
If the performance evaluation shows that the system is underperforming, the following tasks may
be carried out to detect system faults.
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TOPIC 4: TROUBLE-SHOOTING
Introduction to troubleshooting and failure types
A well maintained solar PV system should operate well for many years, but problems
will inevitably arise. This section will tell you how to find the source of the problem
(called trouble-shooting) and suggest how to repair the fault. First, determine what
type of failure is occurring, then follow the tests listed in that table to find the fault
and try the suggested repair procedures.
Failure type 1: if the battery is discharged
That is, if the battery voltage is at 11.5V or below, even after a sunny day, then the fault
is somewhere between the battery and the panel.
Possible Problem
Test
Solar PV Panel or panel
o Disconnect the leads to
wiring faulty
the solar PV panel
terminals of the charge
controller.
o Check the current across
the two wires from the
solar PV panel around
noon when the sun is
shining brightly. If the
current is much less than
0.93A, there is a
problem with the solar
PV panel or the panel
wiring.
o Before checking the
current at PV terminals,
be sure that your
multimeter is in
appropriate current
range
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Repair Suggestions
Disconnect the solar PV panel
and carefully check it for
proper operation (voltage
and
Amperes).
Replace
panels that are not working
properly. Clean all terminals
and wires. Reconnect the
panels being sure the correct
wires are connected to the
correct terminals.
Controller faulty
Wiring between the
controller
and battery is faulty
Check the voltage at the
battery connections and the
panel connections on the
controller when the sun is
shining. If the voltage at the
battery connection is less than
12.5V and at the same time the
voltage at the panel
connection is more than 13.5V,
the controller probably has
failed.
Turn on all the WLED lamps.
Measure the voltage at the
battery terminals of the
controller and the voltage
directly on the terminals of the
battery (not on the battery
connections, but on the actual
terminals of the battery itself).
If the voltage is more than 1 V
lower at the controller than at
the battery terminals, there is a
wiring problem.
Report the problem, so that
the controller can be
replaced.
Disconnect all wires, remove
connectors from battery
terminals. Clean all
connections and wires.
Replace wires in connectors
and terminals and tighten all
connections. Check the wires
to see if they have broken
strands in between the
charge controller and lamps.
Failure type 2, if the battery is charged but appliances are not working
When the battery is charged but the appliances do not work, a wiring fault exists between
the battery and the appliances.
Possible Problem
Test
Repair Suggestions
Fuse
Check the fuse located on
the side of the battery and
charge controller box. If
the fuse is broken, replace
with the new one of the
same value. If it blows out
immediately then there is a
short circuit in the wiring
or WLED lamps. Check all
wiring and lamps.
Fix shorted wiring or faulty
appliances and replace
fuses and reset circuit
breakers.
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Wiring between controller
and appliances
Check the voltage at the
load connections
on the
discharge controller. If the
load voltage is about equal
to the battery voltage, the
fault is in the wiring
between the controller and
the appliances.
Clean all connections,
replace all wires that are
damaged or that are not
the correct size for their
length.
Faulty switches
If there is one switch that
controls all lamps, it may
be the problem. Using a
short wire, connect across
the switch terminals. If the
appliances work, then the
problem is the switch.
Replace the switch.
Controller failure
Measure the voltage at the
load terminals of the
controller and at the
battery terminals of the
controller. If the load
terminal voltage is zero or
much lower than the
battery terminal voltage
(where the voltage at
battery terminals is greater
than 12V), the discharge
controller may not be
working properly.
Replace the controller
Failure type 3: the system works but runs out of power
That is, the “battery low” (red) light on the controller turns on frequently, even if there
was a lot of sunshine that day. This is the most common problem with solar PV systems
and can be caused by many things acting alone or in combination. This type of failure is
an indication that there is not enough charge in the battery to operate the WLED lamps
for as many hours as the user desires.
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Possible Problem
Test
Too little charge from This can be due to shading,
the solar PV panels
damaged solar PV panel,
wiring too small or too long
from PV panel to the
battery, dirty or loose
connections, Solar PV panel
not pointing the right
direction or dirt on the solar
PV panel.
Adding more
This causes the battery to
appliances
discharge too quickly. Using
these added appliances or
other types of lamps may
cause the system to run out of
power
Repair Suggestions
Replace the wires from PV panel to
battery with the thicker ones or
correct ones. Remove the cause of
the shade or move the solar PV
panel so they are no longer shaded
and are pointed correctly, report the
issue and possibly replace the solar
PV panel if damaged, fix the wiring
or clean the solar PV panel
Remove extra appliances,
Operating the
appliances longer
than originally
intended
This takes more energy than
the system was designed for.
The battery is getting
weak and no longer
can store sufficient
charge to operate the
appliances the full
time
The battery should be
suspected if one battery
shows
readings
much
different from the other or
the battery is more than four
years old. If the battery is less
than four years old, its failure
may have been caused by
another problem in the
system. Any time a battery
that is less than four years old
must be replaced, check the
rest of the system very
carefully, be sure that the
solar PV panel is not being
shaded part of the day and
be sure that the user is not
trying to take more power
from the system than it was
designed to deliver.
Advise users that the WLED lamps
should only be operated for less
than 7 hours per day and make the
habit to turn off the ones those are
not in use
Replace the battery but monitor the
replacement carefully. If after the
first month the system once again
does not seem to be providing
power as long as expected, one or
more of the other five reasons for
failure exists and must be corrected
or else the new battery will also be
rapidly weakened and fail. Follow
the procedure mentioned at "Battery
failure" section above.
All of these things may have
seriously shortened the life
24 | P a g e
Note: Users need to be advised that
if more appliances are to be used,
then a separate solar PV system
needs to be installed for those
purposes
of the old battery and if
allowed to continue will ruin
the new battery as well.
Ways to Conserve Energy
Reduce Phantom Loads
Phantom loads refer to when appliances continue to draw electricity when they are "off"
or in the "standby" position. They can draw electricity 24 hours a day and some
appliances draw close to full power just to be on standby. Common examples include:







Computers
Stereos
Televisions
VCR
Glow bars in gas ovens
Electronic phones
Anything with a small "box" on the power cord
A simple solution is to plug into a power strip. Turn off the power strip when items are
not in use.
Energy Efficient Lighting
Besides changing all of your bulbs, there are other things you can do. Low wattage task
lighting can replace high-energy general overheads. Lighter colours on the walls reflect
more light, and solar tubes or skylights can be an added improvement to darker areas.
New higher efficiency standards for light bulbs, most bulbs are required to be 25% more
efficient by using less energy in watts to produce the same amount of light, measured in
lumens.
New Energy Star labelling will show lumens, estimated yearly cost,
expected life, colour, and watts. Look at the lumens for the brightness
you want, and watts for the amount of energy that is used. This will
ultimately make it easier to choose between types of bulbs.
The traditional 100-watt incandescent bulb is being replaced by a 72watt incandescent halogen bulb, which emits about 1,600 to 1,700
lumens. Compact fluorescent bulbs that emit the same lumens only
use 23 watts. While the more efficient incandescent bulbs are less
expensive, the energy savings of compact fluorescent or LED bulbs more than pay for initial
higher
costs.
25 | P a g e
Compact fluorescent bulbs will typically save 2,280 MK/year per replaced bulb (when used
4-6 hours per day). CFL bulbs can last up to 10 times longer than conventional incandescent
bulbs.
LED (light-emitting diode) bulbs provide an optimal light colour that is equal to or better
than incandescent. LED bulbs are more durable and will not break as easily as incandescent
or CFL bulbs. LED is initially more expensive than CFL but can last up to 5 times longer
than
CFL.
Both CFLs and LEDs use about 75 percent less energy than incandescent bulbs, without
sacrificing any light. They also generate very little heat. Look for Energy Star rated bulbs
for the best warranties and longest lasting lights. For instance, in about a year, lower quality
LEDs can become dim and uneven, flicker, shift in colour, or continue to use power when
turned off, among other issues
26 | P a g e
Index
List of Suppliers
1.
2.
3.
4.
5.
6.
Yankho solar
Mawelera
Solair
Kumudzi Kuwale
Recap
Powered by nature
Estimated Component Prices
Solar lamps
Price (MK)
D.light S2
5,900.00
D.light Nova Mobile
9,500.00
SunKing Mobile
19,500.00
SunKing Pico
7,000.00
MB-200 Marathoner Beacon
29,000.00
SunKing Pro 2
28,000.00
Solar rechargeable light bulb
8,500.00
Solar motion light (security light)
35,000.00
Solar lamp with light spreading box
9,000.00
Solar reading light
9,000.00
Solar lamp with panel
16,900.00
Solarway G2 Lantern
18,000.00
Solar home systems
Set of OV camp
Set of OV Beacon
PowaPack Junior
PowaPack Senior (5W)
BS Solar home system
110,000.00
62,000.00
34,900.00
68,000.00
55,000.00
Solar panels
5W
10W
15W
20W
30W
50W
85W
100W
140W
8,000.00
11,000.00
15,000.00
22,000.00
30,000.00
50,000.00
85,000.00
95,000.00
135,000.00
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150W
250W
Batteries
Deltec 6V 1.4 Ah
Deltec 6V 4.5 Ah
Deltec 12V 4.5 Ah
Deltec 12V 7.2 Ah
Deltec 12V 12 Ah
Raylight LeisurePak 50Ah Batteries
Raylight LeisurePak 96Ah Batteries
12v 60ah Omnipower Batteries
(AGM/Gel)
12v 120ah Omnipower Batteries
(AGM/Gel)
Charge Controllers
Steca
Steca 6A
Steca 20A
MPPT
MPPT 10A
MPPT 12/24v 100v 20A
MPPT 12v/24v /48v 100v 30A
MPPT 12v/24v /48v 100v 40A
Landstar
5A Landstar
PWM-AUTO VOLTAGE 12/24V
10A CIEMANS controller
10 A controller with timer
(TE1024N-1)
10 A controller with usb (1024EU)
15A PWM CM1524
20 A controller with timer
(TE3024N-1)
20 A controller with usb (3024A)
30 A controller with timer
(TE3024N-1)
30 A controller with lcd (3024A)
40 A controller with timer
(TE4024N-1)
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140,000.00
4,500.00
7,100.00
15,000.00
18,000.00
26,000.00
59,000.00
99,000.00
129,000.00
219,000.00
25,000.00
65,000.00
70,000.00
125,000.00
213,000.00
289,000.00
9,500.00
7,000.00
16,500.00
17,000.00
18,500.00
28,500.00
29,000.00
35,000.00
42,000.00
65,000.00
50 A controller with timer
(TE5024N-1)
Inverters
UPS
Pure Sine Wave 500W/12v UPS
Pure Sine Wave 1KVA/12v UPS
Pure Sine Wave 2KVA/24V UPS
Tingen inverters
Pure Sine Wave 300W-12v
Pure Sine Wave 500W-12v
Pure Sine Wave 1000W-12v
Pure Sine Wave 2000W-24v
Modified Sine Wave 150W-12v
Modified Sine Wave 300W-12v
Coket
Pure Sine Wave 1500 W 24V
Bulbs
Hong Xing 0.5W
Hong Xing 9W orange lamp
STK bulb 5W
KML bulbs
Hong Xing SolarBulbs
Bramax 7W
Bramax 3W
AC screw 3W
AC screw 5W
Direct bulb 3W
Tough stuff bulb
LED 5watts High Power Bulbs
DC-pin 7W
DC-pin 5W
DC-pin 3W
DC-pin 2W
DC-screw 1W
DC-screw 2W
LED tube 3W
LED tube 5W
LED tube 7W
Outdoor lamp 10W
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75,000.00
150,000.00
203,000.00
343,000.00
65,000.00
110,000.00
185,000.00
320,000.00
15,000.00
38,000.00
445,000.00
900.00
2,500.00
1,500.00
1,800.00
3,000.00
1,800.00
1,500.00
3,800.00
1,500.00
600.00
5,000.00
3,300.00
2,200.00
1,500.00
1,500.00
2,200.00
3,600.00
6,400.00
7,400.00
14,000.00
Outdoor lamp 30W
AC-pin - 3W
AC-pin - 5W
28,000.00
2,000.00
3,500.00
Help Line
For further assistance and inquiries you can contact the Community Energy Malawi Trading Manager on
the following line:
0993888859
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