Basic Usage of Multimeter Module 7

The usage of various common measuring instrument is included in the syllabus. The most commonly used are:

- multimeter
- insulation tester
- bonding tester.

This post is about multimeter. From its name, you can expect that the meter it to measure a number of functions. The most common are:
- AC Voltage
- DC Voltage
- DC Current
- Resistances

There are a number of skills set you need to have to use the meter effectively. There are:
- meter construction theory
- basic electric circuit theory.
- safety practices
- practical skills.

A: Meter construction theory. You can still be able to use the meter effectively even if you do not have any theoritical background knowledge. However you will have a number of disadvantages, for example, you are likely unable to know if the meter is in good operating condition or not.

Basically all meters, in its basic form are ammeters. That means it is operated by current. The way the circuits are wired will determine if it is voltmeter, ammeter or ohmmeter.

B: The basic circuit theory: It is required to assist you in deciding on how to connect the meter. To read the voltage, you have to choose two points to measure the potential different. Thus the voltmeter connection is in parallel. To read current, the meter has to be connect in series with the load.

To read the resistance, the resistor has to be isolated, otherwise the reading will not be accurate.

C: Safety practices: Current can cause death and injury. This mean, you have to know how to work with electricity. Unless you know for certain, assume that the wire or connections have fatal voltage. A voltage as low as 50 volt can cause injury. Avoid wearing conductive rings or watches, as these items can be in contact with life wire.

D: Practical Skills will enable you to handle the equipment and wiring.

Enclosed is a video on how to use a multimeter.