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4:          STATE OF CHARGE OF BATTERIES 
The amount of energy stored in a battery at any time is called the “State of Charge”. 
The  “State  of  Charge”  can  be  approximately  estimated  by  measuring  the  voltage 
across the battery terminals when battery is being discharged under know conditions 
of  current  and  temperature  and  is  the  only  way  to  measure  the  State  of  Charge  of 
sealed batteries. 
 
The  State  of  Charge  of  lead-acid  batteries  that  are  not  sealed  can  also  be 
determined  by  measuring  the  specific  gravity  of  the  electrolyte  (the  acid  and  water 
mixture in the battery) and the temperature of the battery. This is the most practical 
way to measure the state of charge of batteries, which are not sealed. 
 
The following procedure explains how to do this: 
 
1. 

Top up the battery with clean distilled water to the maximum level indicated on 
the battery. 

2. 

Leave the battery for one hour to allow the acid and water to mix. 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Summary of Contents for VC150

Page 1: ......

Page 2: ... I Dulas Solar Powered VC150 Refrigerator Freezer Installation Operation Manual 1 to 26 SECTION II Fault Finding Repair of Photovoltaic Refrigerators 1 to 100 SECTION III A User Handbook For Photovoltaic Refrigerators 1 to 23 ...

Page 3: ...3 SECTION I ...

Page 4: ...4 ...

Page 5: ...ion 12 ELECTRICAL SYSTEM Photovoltaic controller information 13 Photovoltaic controller installation 14 Battery commissioning 15 THE REFRIGERATOR FREEZER Positioning and starting 1 Loading 21 Single fridge controller settings 22 Routine maintenance 23 24 SYSTEM DIAGRAMS Photovoltaic module and battery wiring 25 Diagrams System wiring diagram 26 Refrigerator general layout 27 Electrical circuit dia...

Page 6: ...UCTURE c 1 Unirac rail c 2 Unirac high profile tilt leg kit 2 c 3 Feet 4 c 4 Bolt plain washer spring washer nut Pack c 5 Screws wall plugs Pack c 6 Cable clips BATTERY PACK d 1 Battery 1 d 2 Battery box 1 d 3 Photovoltaic controller 1 d 4 Battery to controller cable 1 d 5 Spare fuses 3 d 6 Cable ties Pack d 7 Padlocks 2 TOOLS REQUIRED FOR INSTALLATION Pozidriv No 2 Screwdriver Slot head Screwdriv...

Page 7: ...ately Clothing exposed to acid should be washed out with water without delay Electrical danger In the case of short circuit extremely high currents can occur which can cause severe burn Block batteries or cells are heavy Ensure secure installation Only use suitable transport equipment Explosion and fire hazard due to explosive gases escaping from the battery Caution Metal parts of battery are alwa...

Page 8: ...or the solar array ensuring that it faces the correct direction is at the correct tilt angle see page on support structure orientation no shading will occur it will not be damaged and it is accessible for cleaning and maintenance 4 Work out the route for the solar array output cable ensuring that there is sufficient length to reach the charge regulator 5 Choose a position for the batteries that is...

Page 9: ...9 KNOW YOUR SYSTEM COMPLETED SOLAR MODULE ARRAY SUPPORT STRUCTURE CHARGE REGULATOR BATTERY PACK REFRIGERATOR SOLAR ARRAY ACCESS GOOD VENTILATION NO DIRECT SUNLIGHT ON REFRIGERATOR 1 2 3 4 5 6 7 8 ...

Page 10: ...he Kyocera junction boxes as illustrated below in figure1 remove plastic unit screw gland in place replace plastic nut and connect cable The array output cable a 2 must then be connected to the nearest module see system wiring diagram brown or red wire to blue or black wire to Ensure that there is sufficient cable to meet the necessary distance then insert into the junction boxes as performed prev...

Page 11: ...f the module Please ensure that the support structure is SECURE AND NOT TWISTED ACCESSIBLE FOR CLEANING WELL VENTILATED SAFE FROM SEVERE WEATHER CONDITIONS NOT SHADED BETWEEN 7am 5 pm The solar array should face towards the equator i e South in the Northern Hemisphere North in the southern Hemisphere The tilt angle of a solar array is dependent on the country in which it is located Figure 3 demons...

Page 12: ...to calculate your appropriate angle and follow the diagram to position the structure accurately Required angle A Approx ratio x y Required Angle A Approx ratio x y 100 6 1 300 2 1 150 4 1 350 1 75 1 200 3 1 400 1 5 1 250 2 4 1 450 1 4 1 Changing the position or length of the Tilt legs can alter module angles Always ensure that all bolts are secured tightly after alterations have been made A protra...

Page 13: ...nt 2 Use 3 8 hardware to assemble the UniRac and hardware to attach the PV modules to the UniRac 3 UniRac must be securely attached to roof rafter ground footing or other secure structural feature Simply screwing the UniRac to roof decking is not adequate to withstand high wind loads 4 leaving as much space as possible at the bottom of the UniRac will minimize debris accumulation and snow load ...

Page 14: ...attachment method for ontaining the proper distance between the mounting feet TILT LEG 6 On UniRacs Tilt Leg Kits rack tilt can be determined by A raising or lowering the Tilt Leg B Moving the Tilt leg up or down alog the UniRails C Adjusting the distance between the lower and upper Mounting feet before final installation COMPLETED UNIRAC TLH HIGH PROFILE TILT LEGS INSTALLATION ADJUSTABLE LEG ...

Page 15: ... the Solar array and support structure wire C The earth wire should follow the shortest and straightest path between the support structure and the earth rod LEVEL 3 FULL LIGHTNING CONDUCTOR SYSTEM Not Supplied Assess the risk of lightening strike Look at other local building are they fitted with lightening conductors Ask local people if TV aerials etc often get struck If the installation is at hig...

Page 16: ...cting system Re connection is automatic A Liquid Crystal Display LCD indicates the state of charge of the batteries and terminals are provided for the connection of batteries photovoltaic panels and the refrigerator OPERATION The Photovoltaic Controller is fully automatic in operation See Steca manual for installation REGULAR FUNCTIONS The display widow on front panel shows system and error messag...

Page 17: ... screws 2 Connect the battery cable to the central pair of terminal on the unit 2 Taking care to ensure correct polarity brown or red to blue or black to 3 The array output cable a 2 must be connected AFTER the batteries to the left hand pair of terminal on the unit 1 brown or red to blue or black to BE AWARE OF LARGE VOLTAGES Cover the array or connect at night 4 The refrigerator is connected to ...

Page 18: ...EN to the battery Secure in place using the nuts bolts and washers provided Insert a spare fuse d 7 into the fuse holder on the battery to regulator cable Any problem refers to the manufacturers handbook provided 3 Apply petroleum jelly or similar to each battery terminal this help avoid corrosion 4 Commence charging of the batteries immediately by connecting the solar array cable to the PV contro...

Page 19: ...ntinuous operation therefore an ON OFF switch is not provided as it is not necessary The VC150 Freezer however does not an ON OFF switch to allow for defrosting This is situated at the rear right of the cabinet as viewed from the front above the cable gland see General Layout diagram The VC150 refrigerator freezer is operational when the power cable is connected to the controller a Strip the power...

Page 20: ...rea remove ice packs Frozen ice packs can be stored in the space inside the wire basket The freezer can freeze nine ice packs simultaneously Remember to switch freezer OFF when not in use to save energy WARNING STANDARD SYSTEMS ARE DESIGNED TO ONLY FREEZE 2 4 KG S OF ICE PER 24 HOURS FREEZING MORE WILL FLATTEN THE BATTERIES VACCINES The refrigerator compartment situated to the RIGHT is in constant...

Page 21: ...perature eg08 Release the controller says Lo Hold the controller gives the low temperature eg03 Release the controller says t1 Hold the controller give vaccines temperature eg06 Release the controller says t2 Hold the controller gives freezer temperature eg 6 Do nothing for 10 seconds and the display reverts to vaccine temperature The temperature alarm has a sound warming beep To cancel press ...

Page 22: ...at the same time WARNING NEVER REMOVE ICE WITH KNIVES OR SHARP OBJECT OR USE SCOURING POWDER ABRASIVE CLEANERS OR STEEL WOOL AS THIS WILL DAMAGE THE METAL PLATING AND CAUSE CORROSION 1 If the refrigerator is to be cleaned move the vaccines into another fridge or a cold box which can ensure the correct temperature is sustained throughout the defrosting process 2 Switch the freezer OFF see general L...

Page 23: ...tention it may need to be re guled or completely replaced alternatively the refrigerator hinges may need adjusting so that the lid is sitting correctly CHECK FOR SHADOWS Any shading of the array solar panels will reduce it s output therefore the array must be checked three times in one day at 7 am 12 midday and 5 pm to ensure all possible shade sources are eliminated Cut back any bushes or trees w...

Page 24: ...24 MODULE AND BATTERY WIRING DIAGRAMS SYSTEM WIRING DIAGRAM ...

Page 25: ...25 SYSTEM WIRING DIAGRAM GENERAL LAYOUT DIAGRAM ...

Page 26: ...26 GENERAL LAYOUT DIAGRAM ELECTRICAL CIRCUIT DIAGRAM ...

Page 27: ...27 ELECTRICAL CIRCUIT DIAGRAM REFRIGERATION CIRCUIT DIAGRAM ...

Page 28: ...28 REFRIGERATION CIRCUIT DIAGRAM ...

Page 29: ...29 SECTION II ...

Page 30: ...30 WORLD HEALTH ORGANISATION EXPANDED PROGRAMME ON IMMUNIZATION FAULT FINDING REPAIR OF PHOTOVOLTAIC REFRIGERATOR A TECHNICIAN S HANDBOOK ...

Page 31: ...ature 2 Electricity 2 1 General 2 2 Voltage 2 3 Current 3 Resistance 4 State of Charge of Batteries 5 Tilt and Direction of Solar Array 6 Open and short circuit measurements on the Photovoltaic Array C MAINTENANCE AND SERVICING 1 Introduction 2 Cleaning the solar array 3 Preventing solar array shadowing 4 Inspection of electrical cables 5 Checking the performance of the solar array 6 Battery maint...

Page 32: ...r 5 Low state of charge of batteries 6 Wiring 7 Solar photovoltaic array 8 Compressor controller 9 Charge regulator 10 Condenser Fans 11 Cooling current 12 Compressor 13 System sizing E REPAIR TECHNIQUES 1 Introduction 2 Replacing a module 3 Adjusting a thermostat 4 Replacing a power cable 5 Replacing the charge regulator 6 Replacing the compressor controller 7 Replacing a condenser Fan 8 Replacin...

Page 33: ...tenance and repair manual supplied by the solar refrigerator manufacturer which define maintenance and repair activities specific to their model of refrigerator Each technician should have his or her own copy of this handbook This handbook is one in a series of technician s handbooks for medical refrigerators and makes reference to other WHO handbooks on compression refrigerators A complete list i...

Page 34: ...rge regulator an electronic unit which is used to prevent the batteries from being damaged by too much electricity from the array or from too much electricity being drawn by refrigerator A compressor which sealed unit A compressor controller which converts D C current electricity provided from the array and or batteries into a form which will drive compressor prevents damage to the compressor if o...

Page 35: ...m on your head attach batteries when transporting them always use a funnel or plastic bottle with a spout to add distilled water BATTERIES ALSO GIVE OFF GASES WHICH ARE EXPLOSIVE make sure that containers provided are well ventilated and that they are placed in a well ventilated room keep naked flames and lighted cigarettes well away from batteries always switch off power from the array and to the...

Page 36: ...here is risk of falling from a roof make sure that the user has an easy and safe way of access to clean the array always use good ladders and position them firmly use crawling boards when walking on roofs FIRST AND MEASURES if battery acid splashes in your eye wash your eye IMMEDIATELY with lots of clean water if battery acid gets on your skin wash IMMEDIATELY with soap and water if you fall from ...

Page 37: ...see pages 37 38 b Layouts of components in some commonly used solar refrigerators are shown in Annex1 Make sure you also have the manufacturers maintenance and repair manual for the refrigerator c REMEMBER There is a risk of electric shock from the solar array There is the risk of acid burn or explosion from batteries ENSURE THAT YOU TAKE THE SAFETY PRECAUTIONS DESCRIBED ON PAGE 34 36 ...

Page 38: ...38 ...

Page 39: ...39 ...

Page 40: ...able and simple to read It is easy to check the accuracy of a bi metal thermometer by removing it from the freezer or refrigerator compartment and placing it alongside another thermometer for several minutes at room temperature If the thermometer gives the same reading then most likely they are reading correctly Thermometers used in the compartments of refrigerators frequently have red and or gree...

Page 41: ...reakage The temperature is read directly from the scale on the thermometer and should be in Centigrade 0 C To take a measurement 1 Put the bulb of the thermometer in the electrolyte and hold it in the electrolyte carefully for about 30 seconds You must be careful not to press the thermometer bulb against the metal plates in the battery because they are delicate and easily damaged 2 Read the temper...

Page 42: ...42 ...

Page 43: ...e DC volts AC volts resistance AC current and DC current It has a digital display and when set correctly is very easy to read The accuracy of the instrument provided in the maintenance kit is sufficient for all faults finding and repair tasks you may need to do There are three basic rules which MUST BE OBSERVED when measure in electricity 1 Voltage is always measured by putting the probes of the m...

Page 44: ...44 ...

Page 45: ...he meter so that it included the voltage that you expect to measure For example if you expect that the voltage you are going to measure will be about 12 V set the range to 0 20V 3 Plug the meter leads into the meter sockets Make sure that the negative black or lead goes into the negative or common socket and that the positive red or lead goes into the positive socket ...

Page 46: ...ou so that you can read it accurately Do not look from an angle b If a meter is a digital type make sure it read 0 0 volts when you touch the meter leads together 6 Touch the metal tips of the meter leads to the electric terminals across which you want to measure the voltage Be careful not to short circuit the terminals by touching both the terminals with the same probe If you short circuit the te...

Page 47: ...bove make sure that the needle points to 0 amps when the metal tips of thermometer leads are not touching anything If the needle does not point at 0 amps adjust zero setting screw until it does Look at the scale with it straight in front of you so that you can read it accurately Do not look from the angle 6 Switch OFF the circuit Disconnect at one terminal the wire through which you want to measur...

Page 48: ...11 SWITCH THE METER OFF after you have finished taking the measurement so that you do not drain the batteries 12 SWITCH OFF the circuit and reconnect the wire to its terminal 13 Switch back ON the circuit ...

Page 49: ... on the current shunt and proceed to measure the mili volt across the current shunt as shown below 4 The value read on the meter in mili volts is converted to current amperes by multiplying this number by the number of amperes which are equivalent to 1 mili volt as indicated on current shunt Example Current shunt is marked 20 A 200 mV Hence 200 Mv is measured if 20 Amps is flowing the wire so 1 mV...

Page 50: ...50 ...

Page 51: ...hich may be indicated 1 b If you want to measure high values of resistance set the range to 100 000 ohms or the largest range of resistance on your millimeter 5 Switch ON the meter plug in the meter leads to the correct sockets in the meter and hold the tips of the probes together 6 If you have an analogue meter adjust the meter so that the resistance between the probes reads zero If you are unabl...

Page 52: ... Charge of sealed batteries The State of Charge of lead acid batteries that are not sealed can also be determined by measuring the specific gravity of the electrolyte the acid and water mixture in the battery and the temperature of the battery This is the most practical way to measure the state of charge of batteries which are not sealed The following procedure explains how to do this 1 Top up the...

Page 53: ...ery so that the bulb of the thermometer is covered in electrolyte but not touching the battery plates Wait until the temperature shown has stabilized and record the electrolyte temperature 7 Using the table below which shows the temperature correction to specific gravity record the correction value Temperature Correction to Specific Gravity Readings to 150 C Electrolyte Temperature 0 C Correction ...

Page 54: ...avity into a measurement of the States of charge by looking at the table below Specific gravity at 15 degrees C Vs State of charge Specific Gravity State of Charge 1 225 100 1 216 90 1 207 80 1 198 70 1 189 60 1 180 50 1 171 40 1 162 30 1 153 20 1 144 10 1 135 0 STATE OF CHARGE TABLE Example A specific gravity of 1 202 corresponds to a state of charge of between 70 and 80 ...

Page 55: ...outh when mounted in the Northern hemisphere and always slope towards the North when mounted in the Southern hemisphere For photovoltaic refrigerator installations neither the tilt or direction needs to be measured with any great accuracy but both should be correct within 10 degrees Array tilt may be measured with an inclinometer which is an instrument designed especially to measure slope or a spi...

Page 56: ...ce where the refrigerator is installed 2 Cut out a triangle from cardboard if you do not plan to use it often or from wood if you have several solar arrays to check DO NOT MAKE IT FROM METAL The triangle should be have one side 50 cms long one angle of 90 degrees and one angle equal to the latitude where the refrigerator is installed ...

Page 57: ...sided of the array and so that the angle which is equal to the latitude points away from the equator 4 Place a spirit level on the upper edge of the triangle If the bubble in the level indicator shows that it is level then the photovoltaic array is set an angle which is equal to the latitude ...

Page 58: ...om the equator 2 Place the compass horizontally on the top edge of the template 3 The magnetic needle on the compass should point along the line of the edge of the template if the array slopes faces towards the equator as it should Also note that The magnetic needle will point down the slope of the panel If your refrigerator is installed in the southern hemisphere The magnetic needle will point up...

Page 59: ...easure the open circuit voltage Voc 2 Measure Voc at around 12 noon on a very sunny day 3 Voc is the voltage across the two output terminals when no electrical current is flowing So you must disconnect one wire from the terminals If you are measuring Voc for the solar array disconnect one solar array output wire from the terminal box If you are measuring Voc for one of the solar modules disconnect...

Page 60: ...hey are short circuited by the millimeter or a shunt You must disconnect one output wire from the terminals when you make this measurement If you are measuring Isc of the solar array disconnect a solar array output wire from the array junction box If you are measuring Isc of one of the solar modules disconnect the module from the solar array at the module junction box 4 After you have disconnected...

Page 61: ...rator if there have been problems with it Inspect the logbook and temperature record sheets to see if a problem is indicated c Enter into the refrigerator log books the date of your visit and at the end of your visit write down the tasks done and measurements taken WHEN YOU FINISH THE SERVICE TASKS a Check that the temperature of the refrigerator is normal b Check all components to ensure the inst...

Page 62: ...t Be very careful when working on the roof Check that access to the array is secure and safe for the user If not make it safe c Use a clean soft cloth wetted with water d Wipe the surface of the solar array gently starting at the highest point and working down to the lowest point e Do not stand on the solar array or lean heavily on it as this may cause damage f Make sure that the person in charge ...

Page 63: ...shes and trees that may start to shade the solar array between 8 00 a m and 4 00 p m Trees and bushes which cause shading only before 8 00 a m or after 4 00 p m need not to be cut down c Make sure that nobody has put anything in front of the solar array that may block the sunshine falling on it d If new building cause shadows to fall on the array it may be necessary to move the array Consult the p...

Page 64: ...igerator socket and the charges regulator terminals strip The connections should be clean and tight If they are loose tighten them If they are dirty take them off and clean them with a wire brush before connecting them tightly b Follow each cable to its end wherever possible Look for the following types of damage the cable has been cut the insulation is worn or the insulation has been eaten away l...

Page 65: ...array see page 52 5 Measure the open circuit voltage of the solar array see page 51 It should be 17 20 volts for a 12 volt system 6 Disconnect one module from the array and measure the short circuit current of the module see page 52 For 12 volt systems the short circuit current in the solar array should approximately be equal to the to the current in a module multiplied by the number of modules to...

Page 66: ... know where to reconnect them c Measure and note in the logbook the voltage of each battery and the of the batteries combined d If the batteries are not sealed they will have plastic stoppers in a row on the top Remove each stopper one by one and see if the metal plates inside are covered by liquid If the tops of the metal plates are above the liquid level add distilled water until they are comple...

Page 67: ...ks on them If they are more than 5 years old order and fit a replacement as soon as possible g Check the wiring connections to the batteries If the wiring connections are loose tighten them If the connections are very dirty or corroded loosen them and clean them with a wire brush before tightening them again h Apply petroleum greases to the terminals i Reconnect the battery cables ensuring they ar...

Page 68: ... has been removed f Clean the refrigerator inside with soap and water and then dry it carefully Never use scouring powder steel wool or abrasive cleaners Remember to clean the lis or door sealing gasket and put some talcum powder on it to prevent it sticking to the lid g Switch the refrigerator back ON h Wait until the inside temperature has fallen to between 00 Cand 80 C i Put the vaccine back in...

Page 69: ...ing a soft brush The condenser and compressor must be clean or the refrigerator will not work properly c If the condenser is fan assisted make sure the fan rotates freely and brush dirt away from the fan and fan motor d Switch the refrigerator ON again e Wipe cleans the outside of the refrigerator using soap and water ...

Page 70: ... care for the refrigerator It is your responsibility when at a health centre to make sure that the user is operating and maintaining the refrigerator correctly c Each refrigerator you are responsible for should have a Daily Record Sheet before starting faultfinding It may help you identify the source of problem d Each solar refrigerator technicians should keep a maintenance Log Book It is importan...

Page 71: ...ning for the motor noise from the compressor but make sure that it is not the noise of the fan if fitted Touching the compressor to see if it is vibrating and Touching the compressor to see if it is hot b The refrigerator is too warm above 80 C and the compressor is running at times c The refrigerator is too cold B 2 Carry out Preliminary Checks These preliminary checks are to be done in order to ...

Page 72: ...ed the thermostat setting to a warmer setting Applies only if the thermostat can be adjusted If it has then reset it at the initial position c If the refrigerator compartment temperature is still more than 80 C proceed step by step through the Fault Finding chart on page 63 SYMPTOM The refrigerator is too cold REMEMBER VACCINE IS DESTROYED IF FROZEN a Some refrigerators have a movable separator be...

Page 73: ...e the fault then move to the next fault in the direction of the arrows Possible fault Fault finding Repair Task No Page no Switched OFF Switched ON User maintenance task D 1 65 Thermostat D 2 67 Fuse in compressor controller D 3 69 Fuse in charge Regulator D 4 71 Low state of charge of battery D 5 72 Wiring D 6 75 Solar Photovoltaic Array D 7 75 Compressor controller D 8 76 Charge Regulator D 9 77...

Page 74: ... the chart If this is found not to be the fault then move to the next fault in the direction of the arrows Possible fault Fault finding Repair Task No Page no User Maintenance Task D 1 Thermostat D 2 Low State of Charge of Battery D 5 Wiring D 6 Solar Photovoltaic Array D 7 Condenser Fan when fitted D 10 Charge Regulator D 9 Cooling Circuit D 11 Compressor D 12 System Sizing D 13 ...

Page 75: ...the arrows Possible fault Fault finding Repair task No Page no Movable Separator replace or repair seperator Between refrigerator and Freezer damaged incorrectly Positioned or removed Applies only to some types Of refrigerator cabinets E g Electrolux RCW 42 Continuous running draw down Switch the Or freezer switches on Refrigerator back Applies only to some types on to normal mode Of refrigerator ...

Page 76: ...led in correctly Check the refrigerator temperature record The refrigerator should ALWAYS been operating above 00 C if there is a record of warning indicator light being lit The warning indicator lights are normally labeled as Do not Freeze Ice Packs and Low Battery State of Charge or Refrigerator Disconnected b Check that the refrigerator is switched ON if not turn it ON c Check that no obstacles...

Page 77: ...om at least 8 00 a m in the morning until 4 00 p m in the afternoon If it is shaded cut back the trees or remove the obstacle If neither is possible it will be necessary for an installation technician to move the solar array to another place where it is not shaded I Check the condition of the batteries 1 Check the level of electrolyte acid and water mixture in each battery cell if the battery is n...

Page 78: ... should be replaced if a battery needs water often more than once in six months then it is either poorly ventilated exposed to direct sunlight or is being deeply discharged in which case its life will be considerably shortened if a water added to a battery is not clean and distilled the battery life will be shortened if the plates of the battery are exposed to the air then they are damaged and the...

Page 79: ...t to its warmest position 4 If the refrigerator compressor continues to run the thermostat is faulty See below for action required 5 If the compressor stops running adjust the thermostat until the temperature in the refrigerator compartment is above 00 Cand below 80 C see page 83 for how to adjust the thermostat Action required 1 Remove ALL vaccine to another refrigerator or cold box with ice pack...

Page 80: ...to terminals T and C of the compressor controller If tightening the connection causes the compressor to run the fault has been repaired 4 Check the thermostat wires are tightly connected to the thermostat unit Mechanical type only If tightening the connection causes the compressor to run the fault has been repaired 5 Check the wires from the thermostat unit to the compressor controller for signs o...

Page 81: ...his temporary wire then The thermostat is faulty or The wires are incorrectly connected or The wires are defective Repair Action required 1 Tighten correct or change the wires 2 If the compressor still does not run CHANGE THE THERMOSTAT in accordance with the manufacturers instructions ...

Page 82: ...h the refrigerator on Some models also have a circuit breaker protecting the refrigerator make sure that it is also switched ON If the compressor now runs the fault is confirmed and has been replaced 7 If the compressor does not run check the fuse again If it has blown against do the actions listed below Repair action require 1 Check that you spare fuse is of the correct type and correct rating 2 ...

Page 83: ...compressor controller from the compressor fit a new fuse and switch on the refrigerator 9 If the fuse does not blows with the compressor socket disconnected the fault is probably in the compressor Proceed with the next steps in the faultfinding Chart to make sure of your diagnosis before replacing the compressor 10 If the fuse blows each time you replace it and switch on the fridge with and withou...

Page 84: ...the fuse holder 3 Check the electrical resistance of the fuse If the fuse has blown take the action detailed below If the fuse has not blown replace the fuse and proceed with the next step on the FAULT FINDING CHART NO 1 Repair action require 1Check that you have the correct fuse 2 Check that the positive and negative connections from the photovoltaic array to the charge regulator are correct tigh...

Page 85: ... have circuit breaker protecting the refrigerator make sure that it is also switched on 7 Turn off the refrigerator take out the fuse and check it If the fuse is Blown then PROCEED TO THE NEXT STEP ON THE FAULT FINDING CHART to find out why the fuse is blowing DO NOT FORGET TO REPLACE THE FUSE LATER Not blown also PROCEED TO THE NEXT STEP ON THE FAULT FINDING CHART This is because the original fus...

Page 86: ...re the voltage of the batteries at the and terminals of the compressor controller The voltage should be greater than 11 5 volts for 12 volt systems 22 6 volts for 24 volt systems if the compressor is NOT running The voltage should be greater than 10 5 volts for 12 volts systems 21 3 volts for 24 volt systems if the compressor IS running 4 If the voltage at the compressor controller terminals is no...

Page 87: ...charger c When fully charged by either method disconnect each battery and leave each battery for 2 hours d Connect the battery 2 batteries for 24 volts system to the refrigerator switch in the refrigerator and measure the voltage between the and terminals of the compressor controller e If the voltage of the battery with the compressor running is LESS THAN 12 5 volts or 25 volts for 24 volt system ...

Page 88: ...sor controller the voltage should be 11 5 to 13 volts if the batteries are adequately charged 23 to 26 volts for 24 volt system 2 If the voltage at the charge regulator and the compressor controller do not corresponds with the above values then there may be wiring fault See below for what action you should take Repair action required 1 Switch OFF the refrigerator 2 Label wires before disconnecting...

Page 89: ...gulator and compressor controller again as detailed above under How to confirm this fault If the voltages are now correct the faults has been repaired If the voltage is still not correct PROCEED WITH THE NEXT CHECK ON THE FAULT FINDING CHART ...

Page 90: ...egulator 4 Measure and write down the short circuit current of the solar array see page 52 5 Measure and write down the open circuit voltage of the solar array It should be 17 20 volts for a 12 volt system 6 Disconnect one module from the array and measure and write down the short circuit current of the module see page 52 For 12 volt systems the short circuit current in the solar array should be a...

Page 91: ... voltage and current of all the modules are similar then there was probably a poor connection on one module or faulty wire Repair action required 1 If a module is faulty replace it as described on page 82 2 If a wiring fault or connection fault between modules is suspected check the electrical continuity of each wire and clean all the wire terminals 3 Reconnect all the modules to the array and che...

Page 92: ...Remove the thermostat and compressor fan wires if fitted From terminals T C and F of the compressor controller Fit a temporary wire between terminals T and C The compressor should then run 2 If the compressor does not run CHECK THE FUSE in the compressor controller again as explained on page no 69 3 If the compressor still does not run change the compressor controller with another of the same mode...

Page 93: ... How to confirm this fault 1 If all previous steps in the faultfinding procedures have not indicated a fault then change the charge regulator see page 84 and see if the refrigerator operates normally for at least one month Repair Action required 1 If after replacing the charge regulator the solar refrigerator works correctly for one month the fault was probably the Charge Regulator ...

Page 94: ...tion you should take Repair action required 1 Switch off the regulator 2 Disconnect the fan wires from the compressor controller Check the continuity of each wire If a break in a wire is detected replace the wire 3 Clean the connections and reconnect the fan wires to the compressor controller 4 Check to see if the fan can freely rotate If it is jammed remove the item that is stopping it from rotat...

Page 95: ...e compressor running hold a lighted match under the condenser outlet pipe until the match is finished c As soon as the match has gone out put your finger on the pipe here the match heater it d The pipe should be warm only The liquid in the pipe will absorb if there is liquid inside the pipe the heat form the match If the pipe is too hot for you to keep your fingers on it then there is no liquid in...

Page 96: ...ct the electrical socket from the compressor 5 Measure the electrical RESISTANCE between the following connections on the compressor plug with your OHMMETER see diagram on Pins on next page Pins No 1 and 3 Pins No 4 and 3 Pins No 2 and 3 The electrical RESISTANCE should be VARY LOW between these connections 6 Measur the electrical RESISTANCE between Pin No 3 and the metal body of the compressor Ma...

Page 97: ...EPS IN THE FINDING CHART HAVE BEEN CAREFULLY CHECKED 2 Replace the compressor in accordance with the manufacturers instructions Refer also to the procedure described in the WHO handbook for COMPRESSION refrigerator repairs Refer to the inside of the front cover of this handbook for details ...

Page 98: ...e system sizing may not be correct The system sizing is incorrect if numbers of solar modules and or the number of batteries are insufficient 2 Check the DAILY RECORD SHEETS to see if large quantities of vaccine and or medical supplies are frequently loaded into the refrigerator 3 Check the DAILY RECORD SHEETS to see that the quantities of icepacks frozen do not exceed the amounts recommended in t...

Page 99: ...rmed and your conclusions that there may be a problem with sizing 3 Send or preferably hand deliver your note to a The chief of the solar refrigerator installation team b The person responsible for solar refrigerator in the organization responsible for the EPI program in your country c Ask your head of department to send a copy of your note to the Cold Chain Unit Expanded programme on Immunization...

Page 100: ...ee part C c Mending a refrigerant leak see part A part C d Recharging the refrigerant loop when the system is undercharged see part A part B e Recharging the refrigerant loop when the system is overcharged see part B f Replacing the evaporator see part C g Replacing a capillary tube see part C h Replacing a fitter drier see part C i Replacing the lid door sealing gasket j Adjusting the lid door se...

Page 101: ...trip Use insulated tools and is careful not to touch the terminals with your hands as you get an electric shock c Remove the lid of the junction box at the back of the faulty module d Mark the positive wire and the negative wire Then disconnect the module output cables from the positive and negative terminals in the terminal box e Loosen the mounting bolts from the module and remove the module fro...

Page 102: ... module terminal box Do not over tighten the lid screws i Reconnect the solar array back to the charge regulator at the charge regulator terminal strip Be careful not to touch the terminals with your hands j Remove the cover or sheet from the solar array k Check the performance of the solar array see page 56 ...

Page 103: ...r compartment after 4 hours The temperature should be 20 C and 40 C c If it is not adjust the thermostat to a warmer or colder setting as appropriate Allow another 4 hours before checking the temperature d Continue adjusting and checking in the same way until the temperature in the bottom of the refrigerator compartment is between 20 C and 40 C REMMBER WAIT 4 HOURS BETWEEN ADJUSTING THE THERMOSTAT...

Page 104: ...y terminals first If the cable is between the solar array and the charge regulator disconnect the solar array terminal first If the cable is between the refrigerator and the charge regulator disconnect the charge regulator first Use insulated tools and do not touch the terminals with your hands to avoid any risk of electric shock f Replace the damaged cable with a new one g Remove the cover placed...

Page 105: ...witch the refrigerator OFF If the charge regulator has an ON OFF switch the charge regulator OFF too b Cover the solar array with a thick cloth or a sheet Make sure that the array is completely covered and be careful not to scratch its surface ...

Page 106: ... negative 3 Solar array positive 4 Solar array negative 5 Battery positive 6 Battery negative f Remove the old charge regulator from its mounting and replace it with the new one Make sure that it is the same type of regulator as the old one g Reconnect all of the wires to the new charge regulator in the following order 1 Battery negative 2 Battery positive 3 Solar array positive 4 Solar array nega...

Page 107: ...rom the battery terminals c Label all the wires you are about to disconnect d Disconnect the wires from the faculty compressor controller in the following order 1 To charge regulator 2 To compressor 3 To fan 4 To thermostat e Unscrew the faculty compressor controller from its mountings f Screw a replacement compressor controller to the mounting If the compressor is made by DANFOSS it must be insta...

Page 108: ... g Reconnect all wiring to the compressor controller ensuring correct polarity in the reverse order they were disconnected h Reconnect the wires to the battery terminals I Switch the refrigerator ON again ...

Page 109: ...h wire is connected to the positive terminal and which wire is connected to the negative terminal Disconnect the wires from the fan terminals d Unscrew the broken fan from its mounting e Screw the new fan into place The new fan must have the same voltage and power ratings as the old one f Reconnect the wires to the fan terminals making sure that the positive wire is connected to the positive termi...

Page 110: ...e type as the old one e Reconnect the wires to the terminals of the new battery Make sure that the positive wire is connected to the positive terminal and that the negative wire is connected to the negative battery terminal If battery terminals of the wire connections are dirty or greasy clean them with a wire brush or steel wool before connecting them f If more than one battery is used in the sol...

Page 111: ...Y RECORD SHEET that is shown on the next page is completed the twice a day By the person responsible for using the refrigerator A MAINTENANCE RECORD SHEET is completed by the repair technician each time he visits a refrigerator installation and performs checks or does repairs This MAINTENANCE RECORD SHEET Is kept by the repair technician It provides a record of repair tasks Each time a technician ...

Page 112: ... REFRIGERATOR COMPARTMENT ABMIENT TEMPERATURE ICE PACKS VACCINES INDICATION ON SIGNAT URE MORNING MONDAY AFTERNOON MORNING TUESDAY AFTERNOON MORNING WEDNESDAY AFTERNOON MORNING THURSDAY AFTERNOON MORNING FRIDAY AFTERNOO N MORNING SATURDAY AFTERNOO N MORNING SUNDAY AFTERNOO N ...

Page 113: ...113 MAINTENANCE RECORD SHEET SIDE 1 NAME OF SITE MAKE AND MODEL OF REFRIGERATOR QUANTITY AND TYPE OF BATTERIES QUANTITY AND TYPE OF PV MODULES POSSIBLE FAULT RESULT OF FAULT FINDING CHECK ...

Page 114: ...ON OF REPAIR MODE PARTS USED NAME OF PART QUANTITY PART NUMBER CHECKED PERFORMED AFTER THE REPAIR NAME OF PART CHECKED RESULT OF CHECK DATE OF REPAIR NAME OF REPAIR TECHNICIAN SIGNATURE OF REPAIR TECHNICIAN SIGNATURE OF RESPONSIBLE PERSON AT SITE ...

Page 115: ...irst space of the left hand column This should be the first item shown on the list of possible faults shown in CHART No 1 CHART No 2 or CHART No 3 in see page 62 to 65 5 When you have followed the procedure for the first faultfinding and repair task description write the result of your work in the space provided alongside the possible fault 6 Proceed to the next fault in the chart that corresponds...

Page 116: ...his procedure is followed no fault should now be evident The results of the checks performed should be entered in the last block of the MAINTENANCE RECORD SHEET 12 Enter date of repair in the space provided at the bottom of the second side of the MAINTENANCE RECORD SHEET 13 Write your name clearly underneath the date 14 Sign the MAINTENANCE RECORD SHEET to verify that the work described on the she...

Page 117: ...g on the job training to the user may be divided into the following 4 parts A ACTION ON HANDOVER The user should fully understand all the actions on handover that are described in detail in PART 1 ACTIONS ON HANDOVER OF THE USER HANDBOOK FOR PFOTOVOLTAIC REFRIGERATOR Actions on handover include a Identifying to the user the basic parts of the solar refrigerator power supply and the basic parts of ...

Page 118: ...r should fully understands how to do simple maintenance which is described in detail in PART 3 USER MAINTENANCE of the USER HANDBOOK FOR PHOTOVOLTAIC REFRIGERATOR Part3 of the user manual is extremely important These are the tasks which the user must do on a regular basis if the refrigerator is to operate correctly These tasks are grouped into daily weekly monthly and six monthly tasks As the repa...

Page 119: ...Check the amount of ice forming around the freezer compartment Defrost if necessary 6 Clean the photovoltaic array 7 Check for shadowing of the photovoltaic array Cut back trees or bushes or remove any obstacles Group 3 tasks normally done monthly by the user 8 Clean the parts of the refrigerator including the condenser Group 4 Tasks normally done every six months by the user 9 Check the level of ...

Page 120: ...ir technician you should talk to and work with the user to make sure that the user can correctly identify the symptoms of a fault Symptoms divide into three basic areas 1 The refrigerator is too warm above 80 C and the compressor is not running 2 The refrigerator is too warm above 80 C and the compressor is running 3 The refrigerator is too cold After you sure the user can identify the symptoms of...

Page 121: ...get warm when it is running This is normal CONDENSER The coil of metal tubing at the back or underneath of the REFRIGERATOR It transfers the heat removed from the refrigerator to the outside air COOLING CIRCUIT The piping and components in which the REFRIGERANT travels It includes the EVAPORATOR CONDENSER and COMPRESSOR COMPRESSOR CONTROLLER The electronic unit that converts the electricity stored...

Page 122: ...argest space in the REFRIGERATOR where the temperature is kept at between 00 C and 80 C this is where vaccines and medicines are stored and is often called the VACCINE COMPARTMENT PHOTOVOLTAIC The name for the way in which a SOLAR ARRAY converts sunlight to electricity PV is a short way of saying PHOTOVOLTAIC PV REFRIGERATOR See SOLAR PHOTOVOLTAIC REFRIGEARTOR REFRIGERANT The fluid that is pumped ...

Page 123: ...ith electricity from a SOLAR ARRAY Also known as SOLAR REFRIGERATOR or PV REFRIGERATOR THERMOSTAT The device that controls the temperature inside the MAIN COMPARTMENT of the REFRIGERATOR TILT ANGLE The angle that the SOLAR ARRAY makes with the horizontal ground VACCINE COMPARTMENT The MAIN COMPARTMENT of the REFRIGERATOR where the temperature is kept at between 00 C to 80 C for the storage of vacc...

Page 124: ...124 ANNEX 1 COMPONENT LAYOUTS OF SOME COMMONLY USED SOLAR REFRIGERATOR ...

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Page 130: ...130 ANNEX II ADDITIONAL EPI TOOL KIT NEEDED FOR PHOTOVOLTAIC REFRIGERATOR REPAIR ...

Page 131: ...tal 10 Amp 10 mV accuracy Ohm 2 shunts 0 200 mV at 0 20 Amps 1 hydrometer break proof 1 compass 1 pair of plastic gloves 1 spirit level 1 latitude template to manufacture on site 1 mercury in glass thermometer range 10 60 0 C 1 protective sheath for thermometer 1 bimetal thermometer ...

Page 132: ... HANDBOOK WORLD HEALTH ORGANISATION A USER HANDBOOK FOR PHOTOVOLTAIC REFRIGERATOR DULAS LTD Dyfi Eco Parc Machynlleth Powys WALES s SY20 8AX U K Tel 44 0 1654 705000 Fax 44 0 1654 703000 E mail solar dulas org uk Website www dulas org uk ...

Page 133: ...voltaic Refrigerator system 116 Operating correctly 2 HOW TO OPERATE YOUR SYSTEM 117 2 1 General remarks 117 2 2 Loading the refrigerator 117 2 3 Filling in the daily record sheet 117 3 USER MAINTENANCE 118 3 1 Daily tasks 118 3 2 Weekly tasks 119 3 3 Monthly Tasks 121 3 4 Six monthly tasks 122 4 WHAT TO DO IF A FAULT OCCURS 125 4 1 The refrigerator is too warm Above 80 C 125 And the compressor is...

Page 134: ...ression refrigerators operating at 12 V or 24 V DC in medical centers These refrigerators are used for storing vaccines and medicine and for freezing icepacks Stand alone means here that the solar array does not power any other device e g lights and the refrigerator is powered only from the solar array This handbook should not be used for any other types of refrigerator ...

Page 135: ...ty by solar cells Figure 1 shows the basic parts of your solar refrigerator Power supply These Parts are the solar Array the charge regulator and the batteries Together they provide the electricity for the refrigerator The solar array can be roof mounted mounted on a pole or located at ground level with a protective fence around it The batteries and charge regulator can be mounted in the refrigera...

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Page 138: ... the charge Regulator and compressor controller are Kept 5 The location of the Refrigerator ON OFF switch 6 When to switch the refrigerator OFF and ON 7 The location and the color of the indicator light REFRIGERATOR DISCONNECTED 8 The location and the color of the indicator light Do Not FREEZE ICEPACKS 9 The location color and function of any Other indicator lights 10 The location and purpose of t...

Page 139: ... level Maintenance on system 4 Data solar refrigerator system installed 5 Make and model of refrigerator Unit installed 6 Make and model of charge regulator Installed 7 Quantity and Type of Batteries installed 8 Quantity and Type of Photovoltaic Modules installed 9 Array Mounting Arrangement Tick arrangement used Roof with means of safe access Pole with possibility for cleaning array Ground with p...

Page 140: ...oft brush to clean condenser Sponge to clean Array Padlocks and keys Petroleum Jelly Battery refill bottle with spout Thermometer to measure refrigerator compartment USER HANDBOOK FOR PHOTOVOLTAIC REFRIGERATORS Manufacturers Manual 11 Name and Address of solar Refrigerator Technician responsible for Maintenance of system 12 How to contact solar Refrigerator Technician VERIFIED AND APPROVED BY Pers...

Page 141: ...D TIME TEMPERATURE IN REFRIGERATOR COMPARTMENT ABMIENT TEMPERATURE ICEPACKS VACCINES INDICATION ON SIGNATURE MORNING MONDAY AFTERNOON MORNING TUESDAY AFTERNOON MORNING WEDNESDAY AFTERNOON MORNING THURSDAY AFTERNOON MORNING FRIDAY AFTERNOON MORNING SATURDAY AFTERNOON MORNING SUNDAY AFTERNOON ...

Page 142: ...ront of the ventilation grill Is the refrigerator cabinet placed so that it is NEVER in direct sunlight Is the refrigerator cabinet raised off the floor so that it can readily be cleaned around and will not be damaged by water used to wash the floor Can you reach the doors and locks easily The Charge Regulator and Batteries Are the charge regulator and Batteries mounted in protective cases Are the...

Page 143: ...net LID close properly Is the THERMOMETER in the refrigerator cabinet showing temperature of more than 00 C and less tan 80 C Are the INDICATOR LIGHT showing that ICE PACKS MAY BE FROZEN Does the COMPRESSOR start and stop periodically IF THE ANSWER TO ALL QUESTIONS IS YES THE INSTALLATION IS CORRECT ...

Page 144: ...ickly and securely c Always lock the refrigerator cabinet immediately after use d Only turn the refrigerator OFF when 0 you need to defrost the evaporator 0 you need to change a fuse e Keep all Vaccines in the refrigerator and in accordance with EPI recommendations The correct temperature for vaccine storage is more than 00 C and less than 80 C NEVER PUT DPT OR TETANUS TOXOID IN THE FREEZER COMPAR...

Page 145: ...s between the cartons of vaccines This allows the cold air to move around the refrigerator compartment f Always keep the same type of vaccine together and store your vaccines neatly g You must use all the old vaccines before the new ones So you should put new vaccines underneath or behind old vaccines Before use make sue that vaccine has not expired h DO NOT KEEP FOOD OR DRINK IN THE REFRIGERATOR ...

Page 146: ...tion 4 of this handbook WHAT TO DO IF A FAULT OCCURS for the action you ust take c Check the ROOM TEMPERATURE and record it on your DAILY RECORD SHEET d Count the NUMBER OF ICE PACKS loaded into the freezer Compartment each morning and record it on your DAILY RECORD SHEET e Count or estimate the QUANTITY OF VACCINES AND MEDICINE loaded into the refrigerator compartment since the last time the DAIL...

Page 147: ...ke b Check the INDICATOR LIGHTS and any other METERS If any of them indicates that the refrigerator system is not operating normally then MOVE ALL VACCINE TO ANOTHER PLACE if FRIDGE DISCONNECTED indicator light is LIT REMOVE UNFROZEN ICE PACKS from the freezer compartment if the DO NOT FREEZE ICE PACKS indicator light is LIT c Make sure that the refrigerator ventilation grill if fitted is not bloc...

Page 148: ...r if possible iv As soon as it is possible to remove ice with your fingers do so Do not remove ice with knives or any other sharp objects v Wipe the freezer compartment dry after all the ice has melted vi Clean the refrigerator inside with soap and water and then dry it carefully NEVER use scouring powder steel wool or abrasive cleaners Remember to clean the lid door sealing gasket and put some ta...

Page 149: ... clean water and a clean soft cloth or sponge Do not scratch the surface of the array iii Wipe the surface of the solar array gently startingat the highest point and working down to the lowest point Make sure that all the dust and dirt is removed iv Do not stand on the solar array or lean heavily on it as this may break it Access to the solar array should be easy and safe Ask the service or instal...

Page 150: ...r ii Remove or open the Cover which provided access to the compressor condenser and fan if fitted of the refrigerator cabinet iii Use the Soft brush provided with your refrigerator to remove any dust and dirt from the condenser and compressor iv If the condenser is fitted with a fan make sure that the fan rotates freely and brush dirt and dust away from the fan and fan motor v Switch the refrigera...

Page 151: ...e started to shade the solar array between 8 am and 4 pm Trees and bushes which only cause shading in early morning Before 8 am or late afternoon after 4 pm do not need to be cut Do not cut down more bushes or trees than necessary and always seek the permission of the person responsible for them by explaining why it is necessary ii Make sure that nobody has put anything in front of the solar array...

Page 152: ...ery then the battery will be damaged and the refrigerator will not operate properly Checks are necessary but following safety regulations MUST be observed KEEP NAKED LIGHTS SPARKS AND HEAT AWAY FROM BATTERIES AS EXPLOSIVE GASES MAY BE PRESENT LIQUID ELECTROLYTE IN BATTERIES IS CORROSIVE KEEP OFF THE SKIN AND AWAY FRO EYES AVOID CONTACT WITH CLOTHES If the batteries are sealed they will NEVER need ...

Page 153: ... a spout or a clean funnel to put in the water iii Replace each stopper or lid iv Do this for all of the compartments in each battery It is important that only DISTILLED WATER is used b Check that The array is firmly mounted All cables or electrical wiring connecting the different parts of the system together are firmly attached and not damaged The battery and charge regulator cases are firmly att...

Page 154: ...e refrigerator and place a thin paper strip over the place where the seal of the refrigerator cabinet comes into contact with the lid door ii Close the lid door iii Pull the paper strip If it moves easily the door lid needs adjustment or the seal needs replacing iv Try the paper stir all around the lid door in this way paying special attention to the corners v Check all the ways around the lid doo...

Page 155: ... the fault you have found out above These CHECKS and ACTIONS are explained in the page of this manual It is IMPORTANT that a You be sure your choice of symptom is correct b You always start with the first step listed on each page and proceed in order through all the steps c If after doing ALL the CHECKS and ACTIONS the refrigerator is still not working properly you start at the beginning and check...

Page 156: ... at the initial position c If the refrigerator compartment temperature is still more than 80 C call the solar refrigeration technician 4 3 The refrigerator is too cold Remember NEVER FREEZE VACCINE If the refrigerator is too cold and the vaccine is in danger of being frozen remove the vaccine to another refrigerator or cold box until the refrigerator temperature is again above 00 C a Some refriger...

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