If you are planning to build your own DIY solar panels to supplement your home energy consumption, one of the basic devices you’ll need is a multimeter. A multimeter is an efficient tool to detect any problems with any electrical devices and it is also used to test the resistance or continuity of an electric circuit. Though this equipment was used, only by engineers or electronic technicians in the past, but now a days it is available in every handyman stores.

It is also affordable and has found a place in everybody’s toolbox. Digital multimeters and analogue multimeters are two different types of multimeters which are available in the market. In a digital multimeter the test readings are displayed in numbers whereas in analogue multimeters display the readings by a value with the help of a needle on a scale.

An electric light may look good but may not function, and then a multimeter is the right device to be used to detect the problem. An important thing that you to be aware of is that it is risky to do any electrical testing while the appliance is connected to any source of power.

Hence the first thing you have to do when working with a multimeter is to see that no live voltage is connected to it. When you are conducting a continuity test after disconnecting the power supply you have to arrange the multimeter to measure resistance. When you are working with solar cells, remember, the cells do generate a charge and you may get a jolt out of it. So be careful!

Using The Multimeter

First you have to set the dial of the multimeter to ohms which is a unit of resistance. You can see two test probes, one which is red is positive and the other a black one is negative. The meter reading will be a zero if you touch the two test probes together.

A zero resistance or a zero reading shows that there is a perfect continuity or there is a closed circuit that conducts current. With this knowledge you can test the continuity in homemade Photovoltaic (PV) panel.

By touching a test probe on the PV cells main string wire and bringing the other test probe into contact with the other end, you can complete the test for continuity test.

A current (amp) reading shows that the solar cells connection is good, any other reading indicates the discontinuity or that the wiring or a solar cell may be faulty and needs to be replaced.

If the circuit is open the multimeter will show discontinuity. It is worth reminding that the power is to be disconnected before conducting any kind of electrical testing. A digital multimeter which is also known as a multitester can be used to test a switch.

You can touch a test probe on each side or pole of the switch. You have to move the switch from off position to on position. If the multimeter reading changes from zero to infinity it indicates that the switch is in a working condition. Because when the switch is in the on position it is not having continuity since the current cannot flow through.

But if the mutimeter reading does not change then your switch has got some problem and you have to fix it. Likewise a multimeter can be used to test a motor also. This can be done by placing a test probe on both the poles. In this test also a zero reading proves the continuity and shows the motor is functioning.

By studying the instructions on the digital multimeter you can do more detailed test too. Multimeters are used to test alternating currents and direct current also along with many other tests.

You can use a multimeter to test a battery by using it on the DC range. Thereby you can find whether the battery is charged. It is worth spending some time studying the basic tests performed by the multimeter so that you can easily figure out the cause of an electric problem that may arise in your daily life. Needless to say whatever electrical tests you perform the priority is to be given to your own safety.

Here is a brief introduction to the process of soldering Photovoltaic (PV) solar cells together. You may be aware that both tabbed and un-tabbed solar cells are available in the market. Though tabbed cells are expensive, it better to use them if you are planning to build many panels.

Not only will you save time, but also benefit in terms of less number of broken cells and frustration. Since the solar cells are very fragile, the chances of breaking them are more. The number of broken cells will be more if you handle more number of cells.

It is important to carry out soldering with utmost care. This is because un-tabbed cells are required to be soldered across a cell. In the case of un-tabbed cells, the work involved is almost double and, therefore, the chances are that you will break some cells.

The free end of the top, sunny-face, tabbing strip is soldered to the bottom of the next cell. This process is repeated down the string. It is, therefore, important to arrange the cells according to the panel layout or design.

For example, it could be 3 strings of 8 cells each or whatever is the design. A gap of 1 centimeter has to be left between each of them. You can, in fact, make a cardboard or masonite template that represents the size of the array box to arrange the strings neatly.

After tabbing the tops, flip them over so that the sunny-side comes down. The tabbing strip can be slipped out from the first one so that it lies over the back of the next. This is to be repeated all the way down the string.

The strip is to be soldered to the contact points on the back of the cells. If you are using cells that look like the ones that I have used, you will see 6 small whitish contact squares.

Flux can be applied to the contact spots after ensuring that tab strips are properly lined up and are sitting over the contact spots. You will have to hold the hot soldering iron to the strip on the spot, touch the solder wire to the point and allow the solder to flow.

Extreme care has to be taken to ensure that too much solder is not applied and the contact is not overheated as it can damage the cell. There is one more way to do this. You can use solder paste on the contact, lay the tab on and keep the iron on the point till it flows. I found this to be a better way of doing it.

This is to be repeated for all the six contact points to have the two cells connected. The whole process has to be done for all the solar cells in the string. Finally, it is important to check that the solder connections have been done properly. This can be done by exposing the cells to light and measuring the output voltage.

It is worth checking at least each string. Otherwise it will be too late to check and rectify. After soldering the string of solders together, you will find that the top tabs are free at one end of the last string.

A short length of tabbing strip will have to be soldered to the back of the first top cell to complete the circuit. There you are! You have a completed a string of solar cells for your use. The number of strings of cells required per panel will depend on the voltage that you want.

It is fun to build your own solar panel, but some work is involved. You may opt to buy a solar panel if cost is not a factor and you don’t have patience.

Do you want to know how to build your own solar panel on a $150 budget? If you do, check out the Power4Home ebook by John Russel. For more information, read up on the Power 4 Home review written some time ago on this blog.

Before you start doing even the simplest electrical wiring job, it is vital that you ask yourself a few very important questions.

Is this something I’m knowledgeable about? How safe is this? Would it be better to ask for a professionals help?

If this is a DIY home solar panel project, it’s necessary that you understand what’s going on, or you may be putting yourself in danger and breaking your insurance policies. If you are thinking of attempting a homemade Photovoltaic (PV) system project on your own, you really should get an all-encompassing DIY solar guide to that type of project.

Even though solar panels themselves are not too difficult to build, for your project to be successful you need to be aware of some technical aspects and other practical points. Depending on a number of things, such as panels, your controller, the storage, and how far your cabling will have to run, you will need to be certain that your cables are of the correct thickness or gauge.

It’s important that the wiring inside the panel and the wiring that leads to the storage system has been done correctly. Also, it’s necessary for the cable to be the right gauge when you connect the solar panel array to your storage system.

An easy rule of thumb, is when buying electrical wire, the smaller the gauge, the thicker the wire will be. To do a proper install on any solar project, you need to ascertain the proper gauge and amperage on each of your wires.

When you run your cables, you will have to find out the power rating of the solar panel and how far the cables will be running to the storage system or the controller. No matter what the electrical wire is made of, it will have some resistance to it.

This resistance will increase as the diameter wire becomes smaller, and as the length of the wire increases. So using the right diameter of wire is vital to your projects success. Otherwise you will suffer dramatic drops in voltage as the electricity travels to the storage unit.

To avoid this, ensure the correct size of wire is used. This is especially true if the run is over 50 feet. Then you will want to use an even lower gauge or thicker wire, in contrast to the wire used in shorter runs.

Another side-effect of using the wrong gauge is that the wires will heat up because of all of the resistance and this will further lessen the voltage that will reach your storage unit. This can also be a severe safety concern. If you suddenly over-load you are at risk of a short out, and a possible fire hazard.

Make certain that you know the distance that the cables will be running, and the size of the load that they will be handling, and you will have much more success.