Constant Voltage Stabilizer - CVT - Explained

I bought 2KVA servo stabilizer from Lotus Autotron , Pune ...
I had given him idea that i'll be using it in house for LCD,Fridge n Comp ...

But when we called electrician for setting it up , he said its 1Phase and for house you need 3 Phase stabilizer :confused: :mad: :sad:

what do i need to do now ?? I paid 5k for it !!
 
Hai,

Connect all the appliances in a single circuit and connect this circuit to the output of the servo.

One point I would like to mention is why do you connect the Fridge to a Servo stab ? Because the compressor will switch ON & OFF many times per hour and every time that load will cause volt drop , which is going to make the servo motor to adjust the Voltage and ultimately the maintanence work in your stab will increase.

Servo stab are meant to be used for precise control of voltage for sensitive equipments like computer and communication equipments.

Just my 2 cents.

N.Murali.
 
Does that mean that the voltage of an ordinary household stabilizer will be jumping?

My hifi (and my wife's laptop) is connected to a small (APC Back-UPS500) UPS, which I was hoping would regulate the voltage as well as provide backup for short outages. However, the amplifier usually trips off on a power cut. It is more sensitive than a computer! Other components remain on.

Whilst I don't want to spend a lot of money on a stabiliser, I doubt that I'll be able to afford the same quality amplifier again, so protection is important.

Normally all the "household voltage stabilizers" which are available in the market will do the voltage correction, but it will not do a smooth correction. Rather those stabilizers should be called voltage boosters. When the output voltage drops from its permissible range, it will give a boost of 30-40v (it will be mentioned in the manual) to keep it in the range and the reverse will happen at the maximum range. So as you told we can say there will be a jump in voltage and it will become worse if the fluctuation is very high and last for a long time, you will hear the continuous "tick" sound from the relays inside.

Whereas a servo stab will have a constant sensing circuit for the output voltage and built in stable reference voltage source. The solid state control circuit operates the motor whenever the output voltage falls or rises beyond the preset voltage (usually it will be + or - 2 or 3v). The motor is mechanically attached (contact using a brush) to the arm of a continuously variable auto transformer for the smooth voltage correction and the movement make the sound. Since the servo motor is correcting the voltage, the correction time will be slightly more compared to others, but it will be smooth and the correction will be within 2 or 3v. If the fluctuation is happening for a long time or it is frequent the motor arm will try to adjust constantly and thereby the wear and tear of the brush will be more and early.
 
there are usu. three kinds of UPSs, off-line, on-line and line-interactive.

off-line UPSs usually are cheaper, lower efficiency solutions. they deliver electricity using the batteries only when there is none from the mains.

line-interactive UPSs are a compromise on cost and quality and are ok for computer use. the crux is the switch-over time (optimally needs to be 5-6ms or then the comp. may reboot, data losses may occur or damage to the electronics is possible).

on-line are the best (among UPSs), for computer and other sensitive equipment needs. this is coz. differential o/p is generated from the batteries, irrespective of the fact that electricity is on or cut, meaning there is waveform correction (square to sine).

so, no AVR needed in on-line. PWM (pulse width modulation) us used.

in on-line UPSs, AC is converted to DC (say input of 230V AC to 180V DC) then AC is regenerated from DC (say input of 180V DC to 220V AC). so, o/p AC is cleaner and constant.

UPSs (incl. on-line) however, are bad choices for audio (since they use a switching frequency of 14.4KHz to 16KHz that could introduce harmonic distortion and noise).

the off-line and line-interactive UPSs need AVRs but the quality of the AVR (or the total lack of it) is a price/market dependent variable.

AVR work using relays for step-up or step-down (physical moving devices).

Line-interactive UPSs usually go upto 1.5KV. Only APC goes upto 5KV.

APCs used to have a lot of issues in India since the designers in the US were not aware of electricity issues here. However, over time, they seem to have customised their offerings for Indian conditions.

coming to servo, correction time, owing to the physical movement of the motor/brush, is approx. 35V/sec where correction in the on-line UPSs is in millisecs. servo also does not do any waveform correction.

consequently, IMHO, for audio use, CVTs are the best option (when not incl. power re-generators in the list of options, like Power Plant from PSAudio). esp. when from companies like Bhurji, that are and have been at the epitome of power conditioning for many years.

CVTs handle harmonic distortion. They handle waveform correction. They work on the saturated core principle so are able to deliver best, clean and stable power. the manufacturer's credentials and R&D are critical to a good CVT design as 'balancing' is a key requirement, esp. since there are 04 coils. and, of course, use of the highest quality of materials.

A CVT, by virtue of its design, is 85% efficient (approx. 15% heat, etc., loss).

Secondly, owing to the large transformers therein, there is an avoidable hum.

Consequently, there are CVT usage best practices, viz.,

1. Try and install the CVT in a room/area other than where the audio eqpt. is, to avoid the irritating hum.
2. Try and keep the CVT atleast 3m away from the audio eqpt. to avoid harmonic distortions.
3. Try and keep the CVT in a well ventilated area to dissipate the heat generated.
4. Depending on the distance of the CVT from the equipment, quality and gauge of the power connecting wire/s need/s to be calculated carefully.

http://www.hifivision.com/audio-vid...ssues-power-supply-inverters-3.html#post32447
 
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Hai,

Connect all the appliances in a single circuit and connect this circuit to the output of the servo.

One point I would like to mention is why do you connect the Fridge to a Servo stab ? Because the compressor will switch ON & OFF many times per hour and every time that load will cause volt drop , which is going to make the servo motor to adjust the Voltage and ultimately the maintanence work in your stab will increase.

Servo stab are meant to be used for precise control of voltage for sensitive equipments like computer and communication equipments.

Just my 2 cents.

N.Murali.

thanks ! :thumbsup:

Servo o/p given to TV , comp n HT ... Fridge excluded because it was on High power socket and I could not give inverter backup to the same :) ...
 
Hello Sir,
i am new to this forum so please co-operate with me. i am a ISP (internet service provider) in nakhatrana kutch. my area is having heavy voltage fluctuations and much more power drops. i have also installed inverter but some times due to lightning strokes the sensitive devices are getting harmed.
so i want to install some powerful devices which will protect my network and networking devices.

I want ur suggestion which device will perfactly fulfill my requirements.?

i want features like line conditioning, constant voltage, over/under voltage protection, surge protection, and all that
 
CVT is best in this regard..
Go for the good companies as some companies gives false ratings.All professional audio guys recommend CVT, even if voltage fluctuation are not there.
Hello Sir,
i am new to this forum so please co-operate with me. i am a ISP (internet service provider) in nakhatrana kutch. my area is having heavy voltage fluctuations and much more power drops. i have also installed inverter but some times due to lightning strokes the sensitive devices are getting harmed.
so i want to install some powerful devices which will protect my network and networking devices.

I want ur suggestion which device will perfactly fulfill my requirements.?

i want features like line conditioning, constant voltage, over/under voltage protection, surge protection, and all that
 
Dear Sir

CVT is based on 30 year old Russian technology

It uses resonance LC principal

During voltage DIP energy from resonant circuit is

extracted and added to output
it provides very good input to output isolation on HF Noise

It is not suitable for use with power amps

Control Circuits, LED Backlit LCD TV, Preamp, Blue ray player are

protected against voltage surges and HF Noise on the line

I am using one ELENT Make 150 VA unit since last 20 years

the 10 Mfd Motor Run Capacitor get dried up after 8-10 years and

voltage correction does not happen, the voltage correction is smooth

like a Servo, but much faster, but it is Bulky and heavy for its VA rating

It does full line isolation which Servo does not do

input noise gets transferred to output in Servo as it is nothing

but Variac, with coupled Motor and control circuit, but high VA/KVA unis

can be wired at EB input to protect Fridge, Washing Machine TV etc

which CVT cannot do do to lower VA Rating

Robert Bose
 
Thanks robert...then why professional audio guys are recommending CVT....Any idea..
I have elent CVT of 1KVA and it is giving good audio signal compared to online UPS..which is being used for my other electronics and difference is audible in terms of harshness..pro audio guys says only for audio CVT, for other electronics UPS is enough

Please read post number 27 in this thread by FM hifiashok...
 
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Which stabilizer with step down transformer 220/ 110 would you recommend for a 51" plasma TV (power consumption wattage 270 steady with 480 watts peak) + Blue Ray Player + Surround sound system 45 watts 5.1?
 
I'm in search for a good power protector for my HT setup; Can I use a UPS instead of Stabilizer? I need to protect my devices from power fluctuations; power backup is not necessary (but ofcourse an added advantage, if price is somewhere similar).

Below are my components to be connected:
TV - Samsung 48H6400 - 48" 3D, Smart LED TV.
Audio - Onkyo HT-S3400 - AV receiver with 630W RMS, 5.1 speakers with passive sub.
Blu-ray player - Samsung BD-H6500
may be I've to add a HD set top box (airtel/ videocon) in future.

Currently these are connected to my 1KVA UPS of Desktop computer; these runs fine.

I've short-listed v-guard Crystal Plus , can all these run with a single V-guard Crystal Plus? Both this stebiliser and USP costs same - around 2800/- so the ups is better deal?

Just got another suggestion for a higher version stabilizer (V Guard Digi 200. It has 6A capacity) price around 3600/-

Also got some advise to use 'online UPS'; which I think costs around 6000/-



Links:
Crystal Plus
http://www.snapdeal.com/product/vgua...bilizer/595052
V-Guard Crystal Plus Voltage Stabilizer - V-Guard : Flipkart.com

DIGI-200
V-Guard DIGI 200 Voltage Stabilizer for Television (Grey) - Buy V-Guard DIGI 200 Voltage Stabilizer for Television (Grey) Online at Low Price in India - Amazon.in
 
Can a Constant voltage transformer(CVT) be used along with a LED TV?Are there any disadvantages of using CVT with LED TVs and are they safe in the long term?
 
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