How to Test an AVR with a Multimeter

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Have you ever thought about why AVRs often malfunction? We can tell that mechanical devices aren’t that best. However, have you ever wondered whether you might be using it incorrectly? 

An Automatic Voltage Regulator or AVR is a protective electrical device created to safeguard pieces of equipment and electronics from voltage surges. It automatically regulates the voltage being provided to specific equipment. 

What is an Automatic Voltage Regulator (AVR)?

An AVR is utilized to control the voltage, as briefly stated earlier. It takes the fluctuating voltage and converts them into a stable voltage. The surge in the voltage typically happens because of the changes in load on the supply system.

Further, the variation in voltage harms the equipment of the power system. The change in the voltage could be regulated by installing the voltage control equipment at different places such as near the feeders, generators, and transformers, among other places.

Note that the voltage regulator is presented at more than one point within the power system to regulate the voltage changes. 

In the DC supply system, the voltage could be regulated by utilizing over compound generators concerning feeders of the same length. Nonetheless, the voltage at the end of every feeder remains constant using a feeder booster in the case of feeders of various lengths. 

Meanwhile, in an AC system, the voltage could be regulated by utilizing different ways like shunt condensers, induction regulators, booster transformers, and so much more. 

What Are the Functions of an Automatic Voltage Regulator? 

Below are the major functions of an AVR:

  • It accelerates the excitation of the system under fault circumstances, so the maximum coordinating power exists at the period of clearance of the fault 
  • The automatic voltage regulators lower the overvoltages that take place due to the sudden loss of load on the system
  • It separates the reactive load among the alternators working in parallel
  • It regulates the voltage of the system and has the machine’s operation closer to the steady-state stability 

Are you thinking about what will happen when there’s a sudden variation in load within the alternator? There must be a change in the excitation system to offer equal voltage under the new load condition. That could be done by using an automatic voltage regulator. 

Bear in mind that the automatic voltage regulator equipment runs in the exciting field. It also alters the exciter output voltage as well as the field current. The ARV doesn’t provide immediate response during the wild fluctuation.

The fast-acting voltage regulators based on the overshooting of the market principle are utilized to get the immediate response. In this principle, the excitation of the system increases when the load increases. The regulator lowers the right value’s excitation before the voltage rises to the value corresponding to the raised excitation. 

When Should You Check Your AVR? 

There are common signs that will tell you if your AVR needs immediate testing. Some of the common signs are the following:

  1. Excessive power surges

Does the generator experience a huge amount of load and power? There are high possibilities that your AVR will also experience a shock. The reason behind that is that your automatic voltage regulator will not stabilize the voltage due to unexpected changes in massive power quantity. 

  1. Overload

Yes, overload is one of the major culprits as to why your AVR is malfunctioning. You will find a decline in motor speed when a generator is supplied with a more electric load than it’s supposed to deal with. That, in turn, causes the voltage to decline. 

Thus, your AVR will continuously try to keep the set voltage. That overextends the AVR, and if it continuously happens, your AVR is guaranteed to stop sooner than you anticipated.

  1. Short circuit

Did you know that short circuits are considered to be deadly not just to your AVR but to your generator as well? Frequent incidences of short circuits will require the automatic voltage regulator in your generator. 

  1. Uneven generator engine speed

Ultimately, your AVR will work twice as hard to compensate for the uneven rotations when the generator’s motor has uneven revolutions per minute. That will only cause damage to your AVR in the end.

Hence, it will help if you seek a professional that will check your generator. Do this once you observe your generator is not working properly. 

Practical Steps on Testing Your AVR with a Multimeter

You know firsthand that a malfunctioning AVR could cause permanent damage to your generator. That’s especially true if you didn’t sort it out as soon as possible. Here are the steps you need to take to determine if your AVR is okay or not. 

  1. Check the voltage from the input pin to the ground.
  2. Test the voltage going into the voltage regulator. Take your multimeter and insert it in the DC voltage setting.
  3. Take the probes and insert the positive on the input of the AVR and the negative on the ground pin. 
  4. The AVR is receiving enough voltage to regulate down if you see a higher voltage reading. 
  5. If the regulator is rated to the output of 5V, you should read a voltage close to 5V coming out from the output. 
  6. To measure the output voltage, put your multimeter set in the DC voltage and place the positive probe on the output pin of the AVR. The negative probe on the regulator’s ground pin.
  7. You should now read a voltage at or about the rated voltage the AVR is designed for. 

Final Thoughts

Excessive changes in the electricity levels coursing through your home might take place at any time. That could harm many of your electrical devices, obliging you to pay costly charges for its repairs. To make things worse, such surges could also cause short circuits, which could cause a fire in your property. 

Choose to safeguard your electrical appliances today from power outages, short circuits, and power surges by getting an AVR today. If you think your AVR is malfunctioning, just visit this article again so you know how to test it.

We hope you find our article highly informative. Leave your thoughts by writing your comments below.

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