How to determine kVA for my house? (to buy a servo stabilizer)

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To determine the kVA needed for a home with a treadmill featuring a 3HP AC motor, it's essential to consider the total load and voltage fluctuations. The manufacturer recommends a servo stabilizer for the motor, which should support at least 3kVA. Given the sanctioned maximum load of 60A at 230V RMS, and accounting for two air conditioners and a microwave, a calculation of the remaining load is necessary. Voltage fluctuations can drop to as low as 180V during peak usage, highlighting the need for a reliable stabilizer. Investing in a servo stabilizer for the entire house may be beneficial for protecting appliances from these fluctuations.
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I just got a treadmill delivered. It is semi-commercial with a 3HP AC motor that can go to 6HP at peak. The Amazon product page said that a stabilizer is recommended. We live in a metropolitan city, so voltage variations aren't too much, but we do have sudden fluctuations once in a while, and steady low voltage in the summer when everyone is using air conditioners. So all costly appliances like air conditioners and refrigerators have relay-based stabilizers. But for a 3HP motor, only servo stabilizers will work. I had a word with the manufacturer; they said it's better if I buy a stabilizer to protect the motor and MCB, and of course, he also confirmed that it has to be a servo stabilizer. I should be buying one that can support a minimum of 3kVA.

The thing is, servo stabilizers are costly. I was wondering if it is logical to pay a bit more and get a servo stabilizer for the entire house. ("Entire house" excludes air conditioners and microwave oven, but includes the refrigerator.) We have a sanctioned maximum load of 60A (at 230V RMS mains). Deduct two air conditioners and one microwave oven; each takes about 11A at peak. With this data, how do I calculate the kVA for my house?
 
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What is your supply voltage and frequency?
How much variation of voltage do you see ?

A servo based stabiliser transitions smoothly, without interruption to the supply. A relay based stabiliser, will have short periods of interruption while switching, when there is no power output. That may reset a controller or computer system.

The third way is to use a VFD, variable frequency drive. That should produce a steady output at the mains frequency and voltage expected.
 
Baluncore said:
What is your supply voltage and frequency?
220V RMS @ 50Hz.
Baluncore said:
How much variation of voltage do you see ?
Sudden fluctuations can go down to 190V; in summer, during high usage of air conditioners, we have seen it go to 180V.
 

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