[anupmathur]

Originally Posted by khoj

.... Overkill? maybe but better to be safe(r) than sorry.

Hmm, I'm not sure if it just overkill or a case of losing sight of the wood for the trees.
Apart from very high first cost, CVTs have poor efficiency at low loads; and an inverter AC will work at low loads for considerable lengths of time.
CVTs invariably make a humming sound and can certainly not be kept inside the room because of this AND the fact that they generate a fair amount of heat due to the saturated core.

So what exactly are we trying to achieve? Saving on the electricity bill? Is it likely to be achieved with this set up? What sort of time frame are we looking at for pay back, if all goes well and there are no nasty surprises?

You'd have to also make sure your CVTs have sufficient redundancy built in by way of capacitors and that the capacitors used are of high quality.

[Aroy]

Even I think that the whole point of buying an Inverter AC is lost when you use CVT. Apart from HUM, depending on its peak voltage rating a CVT will dissipate power to an extent of 30%, as well as produce "chopped" waveform at higher voltages. In case you are apprehensive of power related failures in AC, your best option will be buy an "Old Style" AC - Compressor, fan, mechanical thermostat and two rotary switches. Properly maintained this will never fail, as there is nothing to fail (the compressor has a high current cut off switch, which can be replaced at a nominal cost). Yes the compressor will ultimately wear out (not fail), but that is years of steady service away.

In case you have a lot of equipment with electronics (including modern AC, Refrigerator and Washing Machines), a better idea is to invest in a central facility which will control the power. A high power on-line UPS with over/under voltage protection with a nominal battery backup of 10 minutes is ideal solution. Then you can do away with all sorts of expensive AMC, which will amortize the cost of the 10/15KVA UPS.

[mykal shoemaker]

Originally Posted by anupmathur

I dare say it is more to do with planned 'obsolescence' or planned failure. The world has become very greedy.
And process control is so good these days that almost every aspect of performance or non-performance can be controlled to a remarkable degree.

I would like to point out that today's electronics CAN be made very very reliable, IF the intent is there. Sadly, it is only commercial considerations that drive the consumer market of today.
Such is not the case with products made to, say, mil specs.

The good old honest to goodness product cannot be found in today's marketplace.

Agree with this.I have noticed multiple laptop batteries or components failing exactly after warranty expiry. (Mostly within same month or next month). I always had a doubt on this.It looks like ,these are becoming a standard now.

[Thad E Ginathom]

It must take amazing skill to design a component to last 13 months!

And yet, it does seem to be very common

[khoj]

So how about I use a Servo stabiliser right at the meter. Will this be better or just another more expensive CVT?

Originally Posted by anupmathur

Hmm, I'm not sure if it just overkill or a case of losing sight of the wood for the trees.

Originally Posted by Aroy

Even I think that the whole point of buying an Inverter AC is lost when you use CVT.

[anupmathur]

Originally Posted by khoj

So how about I use a Servo stabiliser right at the meter. Will this be better or just another more expensive CVT?

I do believe that the answer does not lie in trying to create input mains amplitudes and waveforms that are suitable to 'protect' the product. That onus must always be with the manufacturer. If the product requires such additional gadgetry to operate successfully I consider that to be a failure of the manufacturer.
There are LG fridges in the market that have a large sticker on the front saying 'Stabilizer not required'.

The only gadget, perhaps, that could be needed (and because this is India) is a voltage protector, which would interrupt power in the event of abnormally high or low voltage and brown outs. There is no reason why a manufacturer should not incorporate such protection in the appliance; this is a very inexpensive set up.
Any other protections ought to be built in by the maker. If not, I would stay away from such a product, and I would spread the word.

[inder]

I am installing two AC's at my village farm house where the voltage fluctuation is an issue. I called the electrician to do the wiring first,he has suggested an AC box. Something like this http://www.snapdeal.com/product/have...cket/682216429
I wanted to know since the AC box has an MCB , do I need to install a Stabiliser for the AC??

[Aroy]

Originally Posted by inder

I am installing two AC's at my village farm house where the voltage fluctuation is an issue. I called the electrician to do the wiring first,he has suggested an AC box. Something like this http://www.snapdeal.com/product/have...cket/682216429
I wanted to know since the AC box has an MCB , do I need to install a Stabiliser for the AC??

MCB and stabilizers are two different things.

Stabiliser will control voltage, stepping it up if input is low and stepping it down if input is high.
MCM is just a switch which cuts off if high current passes (short circuit protection).

In your case you need
. Stabiliser to control voltage
. Socket with MCB to connect the AC to mains
. High Voltage protection - Surge protector, to ensure that voltage spikes, which can fry AC electronics are suppressed.

Alternatively, you can get an assembled AC, which has only electricals and no electronics
- Compressor
- Mechanical Thermostat
- Fan
- Two rotary switches. One for Off-Fan-Compressor. One for fan speed settings. Thermostat comes with its own rotary controller.

The advantage is
. No electronics, hence immune to voltage fluctuations (low voltage will only decrease cooling).
. With lower density condensers, means that they will clog less, easier cleaning.
. If you get a split version, then the indoor and outdoor units can have lerger condensers, making the AC more efficient.

The only disadvantage is the efficiency, it may consume 50% or more power than a 5 star AC, unless you have split unit with over sized condensers at bot ends.

[inder]

I think a stabilizer would be better than an assembled AC.

[diyguy]

Originally Posted by Aroy

. High Voltage protection - Surge protector, to ensure that voltage spikes, which can fry AC electronics are suppressed.

Any idea what sort of surge protector can be installed for an ac line?

[inder]

One more question. Is it advisable to install the outdoor unit at a level 4-5 ft below the indoor unit.

[anupmathur]

Originally Posted by inder

I think a stabilizer would be better than an assembled AC.

Originally Posted by diyguy

Any idea what sort of surge protector can be installed for an ac line?

I think this will suffice for your AC:

http://www.snapdeal.com/product/soll...oltage/1356193

Any AC being sold in India can withstand voltage fluctuations between about 170 to 270 volts.

[diyguy]

Originally Posted by anupmathur

I think this will suffice for your AC:http://www.snapdeal.com/product/soll...oltage/1356193

Thanks that has an inbuilt surge protector and stabilizer. We're hearing of many inverter AC with board failures that are costing a lot to fix. Maybe good one to use for those models.

[inder]

I have shortlisted Daikin FTC 50 QRV which mentions stabilser free operation. Should I still get a Stabiliser or the product mentioned above

[anupmathur]

Originally Posted by inder

I have shortlisted Daikin FTC 50 QRV which mentions stabilser free operation. Should I still get a Stabiliser or the product mentioned above

Strictly speaking you should take the manufacturer on his word.
However, the Sollatek can do no harm.