Why should we need stabilizer for our home appliances?

“Power supply is erratic at most places in India, with voltage fluctuating in both directions (up and down) at many places frequently. These voltage fluctuations can damage appliances, there by causing them to end much before their normal useful life. When voltage goes down, electric current in the appliance increase, which can result in burning of the appliance. Voltage Stabilizers have thus found place in many homes and offices in India. In this article we will talk about voltage stabilizers: what they do, how much power do they consume and how to select one for your setup.

What are Voltage Fluctuations and why do the happen in your home?

Voltage fluctuations are changes (increase or decrease) in voltage coming to your home that make the lights glow dimmer (for low voltage) or brighter (for high voltage) than normal depending. Typically they are not dangerous for most of the appliances, but then they do damage appliances with motors. But then they certainly vary the output of the appliance.

Reasons for Voltage Fluctuations in your home

Voltage Fluctuations typically happen because of bad wirings (to your house or inside the house), overload (be it you using more power than your sanctioned load or your neighbors using more), sudden switching on of high powered appliances (like air conditioners, motors), bad eating, or short circuits. Whenever you experience voltage fluctuations, do check for any of these reasons.

What are voltage stabilizers and how do they fix (avoid) voltage fluctuations?

As the name suggests, voltage stabilizers stabilize the voltage, which means if the supply voltage fluctuates or varies (is less or more than the acceptable range), it brings it to the desired range. It does so by using electromagnetic regulators that use tap changers with autotransformers. If the output voltage is not in range a mechanism switches the tap, to change the transformer to move the voltage in acceptable range. It does not give a constant voltage output, but operates the system in a safe voltage range.

How to choose a right sized stabilizer?

Sizing of a stabilizer is very similar to sizing of a UPS or Inverter (power backup). The most important thing is to know the load connected to the stabilizer. First you must note down the power (or watts) for all the appliances that will be connected to a stabilizer. The sum total of the power consumption (or watts) will give you the load on stabilizer in watts. But most stabilizer sizes are in VA (Volt Ampere) or kVA (kilo Volt Ampere which is equal to 1000 Volt Ampere). Although to get to actual VA (or Volt Ampere) from Watts  you will have to do some measurements, but to give a rough approximation, you can increase the Watts value by 20% to get the approximate VA size that you may need.

So for e.g. if sum of watts connected to your stabilizer is 1000 then you can take a 1200 VA or 1.2 kVA stabilizer. (Please note that 20% is suitable for residential systems and may not work in industries if your power factor is bad).

Important things to look for before buying a voltage stabilizer?

Before buying a voltage stabilizer the most important thing that you should make note of is the input voltage range that you get in your house. This is important because every stabilizer has a minimum and maximum input voltage to which it can stabilize the output voltage. If a voltage stabilizer has input voltage range of 150 V (min) – 260 V (max) then if the voltage in your house goes below 150 V or more than 260 V, then the stabilizer will just cut off the power supply to your appliance. But if it is 160 V or 250 V (within the working range), then it will try to stabilize it to the desired output voltage range.

Cosmostat is reputed name in India for Manufacturing of Servo Stabilizer


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