Some insights on voltage stabilizers. Usage, types blah blah

Discalimer: This is only meant for informational, not a final advice for your requirement. Stabilizers(voltage) are a type of electrical device used to provide a constant(regulated) voltage at output irrespective of any change/fluctuations in the input. The very basic purpose is to protect the connected equipment (say a TV, refrigerator, air conditionser etc) from probable damage due to voltage surge or flucuations, over or under voltage instances. There are different kinds of stabilizers in market, and I will try not to point any specific but enlighten on different aspects. Basic type: The basic ones cost varies from 1-3k depending on its capacity. They regulate the incoming voltage based on certain range. They allow any incoming voltage if its falls with in the safe range (say 200-240). If it senses the voltage going out of the range (lesser or higher), it will trip off the output. This way the equipment connected will not see any low/high voltage, and keep it protected. Advanced type: These usually cost starting from 4-5k With advancements in technology, and the availability of micro processors, power electronic devices changed the way we see a voltage stabilizer. Now we have advanced versions with intelligent features like ultra fast response to fluctuations, buck and boost operations to compensate during over and under voltage conditions. In the name of boosting, one should not expect unrealistic boost operation. Most units available in the market boost the voltage by 60V max. So if there is a low voltage condition say 150V, the stabilizer will boost the output to about 210V. If the input happens to be at 120V, it my cut-off the output saying low voltage. This can change from manufacuterer to manufacturer. In my opinion, these are invented with the problems we bought upon ourselves. During night times, with extensive usage of air conditioners, the voltage goes low due to excessive load on the grid. Traditional ACs doesn't function during such instances. The new variant stabilizers has buck/boost regulators in it. A buck regulator decreases the output in case of higher voltage, while boost regulator increases the voltage in case of low voltage. Along with this, they also usually have fast response to surge/spike conditions, and other intelligent features like over current, thermal protections. Although the technologies(buck/boost) used inside are quite old when it comes to power electronics, they are new to this application area. Thus it may work flaw-less with some users, and may create problems with other users. Manufacturers learn from the field failuers, and may optimize their design to suit the needs. Now the most controversial topic. Does modern electronic devices need stabilizer? Modern electronic devices like LED TV, or inverter type Refrigerator, washing machine, air conditioners use SMPS technology for the appliance power requirements. SMPS technology can easily accept 110-290 working voltage. Please refer to your appliance user manual or electrical diagram stuck on it to understand the actual working voltage of appliance you are dealing with. With that mentioned, they don't really need a stabilizer to function. Most consumers are brain washed to buy a stabilizer for their modern devices. Ofcourse there are certain situationS where it is suggested to use a stabilizer. Your TV can get damaged due to Power Surge, which is happening at unexpected moment due to the occurrence of lightning or if the power line is damaged. Hence to protect your LED TV from those surges and also from the extreme high voltage fluctuations, you need to use a voltage stabilizer with surge protection. But if you can stay from not using the TV during such instances, you may not need a stabilizer. Other than that, the usage of stabilizer can be location specific. Urban locations, usually, have a much stable supply voltage, and thus pose no electrical threat to the TV. So, no voltage stabilizer is required. A genuine "spike-guarded power strip" can be handy. Rural places may sometimes have voltages as low as 90. The TV may or may not work, but no damage is expected. Here the latest variant stabilizer is required to operate the TV. The problematic zones are the places where large industries/factories are situated. Here, the power supply voltage can be unpredictable, with a few dangerous spikes here and there. In such cases, it is advised to use a automatic voltage stabilizer along with a spike buster for added protection. Coming to stabilizer for air-conditioners: So where is the need? Most air conditioners generally have a 5 minute time delay before the compressor starts after the ac unit is powered on. This wait is recommended to prevent compressor from short cycling. In simpler words, the compressor need to wait for the pressure to balance. The compressor compresses the refrigerant and pumps out at high pressure. As the compressor runs, it develops high pressure on one side and low on the other side. When a compressor is restarted right away, the compressor(atleast the ones' that are used in air conditioners) cannot start working against the existing high pressure. In general, 5-7 minutes is a good time enough to balance the pressure, so that compressor can start working. This nature of compressor is common among traditional and inverter acs. If you notice, stabilizers used for refrigerators, air conditioners don't immediately enable output after they are powered on. The output is enabled after a defined time (say 3-5 mins). This is done to accomodate the 5 minute time delay that I discussed earlier in case of compressors. But this very need is also addressed in refrigerators/ air-conditioners via some thermostat or other technologies. If it is not done in the appliance you have, it is recommended for a stabilizer to take care of the required time-delay. I've observed a whichever inverter model I came across, and in all of them, there is a time delay in starting the compressor during the event of power interruption. I've several other data points where manufacturers ticked this feature in inverter models. Which stabilizer type for inverter, non-inverter air-conditioners? As already mentioned inverter variants have good range of working voltage, hence can operate in low voltage conditions too. So in my undestanding, one doesn't need the advanced type, a basic type with surge protection can take care of appliance in the event of electrical surge. For traditional(non-inverter) type air-conditioners, the compressors are induction motor type and hence they cannot function unless it has the working voltage (200-240v) available. In the event of low voltage, an advanced type of stabilizer will help in boosting the voltage, and enabling the appliance. But if one wants a basic surge protection, a basic type also will do, but in the even of low voltage, the air-conditioner cannot function. Bottom line: Go for reputed manufactures, or if you have an idea what you are dealing with, then local-made. They have fewer sockets, shorter wires, compared to the fake ones. Also in case of TV, invest in a proper surge/spike buster as an additional level of protection. The same may not be available in high power ratings to suit air-conditioners, so please do not use the ones meant for low power rated devices like TVs. Other titbits In my home, I do not have a stabilizer for my LED TV or inverter type refrigerator. I live in a place where there is no need for air-conditioner. There is an instance when my aunt bought a TV, she asked which stabilizer should I buy. After explaining the theory behind stabilizer's need in layman terms, I gave her two options. 1. Do you want to believe in science and do away with stabilizer? 2. Or do you want to believe in stars/forces etc and use a stabilizer? She went with option 2 and I ended up suggesting her a model for the same. Also in my native (a village), we have a 43", and it doesn't have any stabilizer in its path.