If you work in the electrical industry, then you need to make sure that you know your way around a multimeter. This very handy tool is a device that electricians and electrical professionals have to rely on when it comes to checking circuits. This is why it is important that you have a good idea how they work and how they are supposed to be used to allow you to maximize them in the many activities that you get involved with.
Almost all of the multimeters that are sold in the market these days are designed to measure resistance, current, as well as voltage. Some of these units have a continuity check. When they do, this will often result in a loud beep if it establishes that two things are connected electrically. This makes the device very helpful especially during those instances when you may be building a circuit, connecting wires, or of you are soldering. The beep coming from the meter gives you the assurance that you are on the right track and everything is in place. This is also a handy tool for these instances when you want to be sure that two points are not connected.
There are multimeters that have a diode checking function. Diodes are one-way valves that only allow electricity to flow through in a single direction. A multimeter can be very helpful in determining which direction the flow of the current on the diode is going and it is handy too in ensuring that the diode you are using is indeed in the proper working state. Reading the manual that the multimeter came with is always very helpful if you want to get a full description on how the diode check is supposed to work.
Depending on the design of the device, there are also those that may be fashioned to perform other functions. For instance, there are those multimeters that are used to identify and measure other components such as capacitors and transistors. Not every multimeter out there will have all these features, though, so, it is always best that you assess ahead of time what specific functions you will need to use the multimeters for for you to pick the right one that you need.
You will need to look for the right units out of all the choices that the market can provide you with; it is a good thing that your options are plenty as this means that you can shop around and find a device that will be the most useful for you. Use this opportunity too to anticipate not only your needs now but your needs for the device in the future for you to select one that you know will last the test of time.
Check the reviews. You will find that it would be easier to pick out the best items when you have the feedback from past users to back on, if these people have actually used these times before, then you can get a good glimpse of how they found the experience- whether they were satisfied with the way it worked or not.
Different types of multimeters are designed with various levels of protection against the typical electrical hazards just like different types of helmets are designed to protect against labor, rock climbing or motorbike accidents. So just for your own safety you must to choose a multimeter that’s designed to protect against harmful hazards that you are most likely to face.
Things That You Must Consider
When dealing with the electrical measurements in a building you need to consider three basic characteristics. First and foremost the voltage rating which in these types of applications is known by electrical professionals is usually 230 or 477 V. Now you need to use an appropriate multimeter to measure the voltage that is expected to be present. In the second characteristic you need to consider the transient voltages when choosing a multimeter because you cannot judge everything just by considering the voltage. The transient voltages usually originate from natural causes like lightning outside the building or produced by switching operations on the power distribution system. So the multimeter should always be designed to endure these peak transients safely. The third characteristic is that you should also consider the circuit’s energy capacity. As the higher current circuits have the tendency to deliver more energy into a fault than the lower current circuits so the measurements done on higher energy circuits are way more hazardous than measurements done on the lower energy circuits. So you should always prefer a multimeter that is appropriate for the circuit’s energy capacity.
Arc flash is basically the result of a very usual mistake when using a multimeter that has some pretty serious consequences. Usually an electrician wants to do a current measurement and then want to measure the circuit voltage but he forgets the most important element to switch the test leads from the initial terminal to the voltage terminal. When the test leads tend to touch a live terminal then a high current will flow through the test leads and the meter. This fault current can turn out to be hundreds of amperes if you’re working in an area having low circuit impedance. The meter circuitry along with the test leads cannot sustain such high currents and open circuit will happen in the meter. When this happens then an arc will be made through the open part of the circuit and if it’s not immediately controlled then the arc will force the air in the vicinity to become superheated and converted to plasma. Now this is known as an arc flash and it releases a lot of energy in most of the cases.
The makers of high quality handheld multimeters have tackled the issue by introducing a special kind of high energy fuse in the meter to restrict the arc flash within the fuse before it tends to spread outside the meter. Today’s product safety standards insist on handheld multimeters with comprises of this special type of fuse on the current input circuits.
Always choose the hand held multimeter by considering the trustworthiness of manufacturer. If the manufacturer shows you a declaration of conformity only then purchase the hand-held multimeter.