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.