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New model of power kavach : 3kva with 3 pin socket output

We are looking for dealers all across India to reach out to customers who have faced neutral open and spikes related problems.

Click here To know more about power kavach

Please reach out to us on 9769996205 or email us on

VMC machine PCB damaged inspite of having a stabilizer

We had a case where a VMC machine already having a stabilizer installed for it. However one of PCB was damaged in spite of having stabilizer. This is situation that happened after 4 years of installations. The stabilizer was from reputed make and was in good working condition. The VMC machine is from reputed international make.

Why did the VMC machine get damaged inspite of having stabilizer installed?

A servo stabilizer is voltage conditioner which stabilizes or brings the voltage to set point even if there any variations in voltage in the input. So if you want a stable supply then you will need a Stabilizer

However Stabilizer has 2 major limitations.

1. Response time: If the voltage shoots up to above 300V in any phase, the stabilizer will take atelast 6-7 seconds to cut off the supply to the equipment. In one second 50 cycles of high voltage supply pass in to the equipment and this can damage the equipment. So you need something that can cut off immediately when this happens.

2. Spikes: In a normal day , your equipment faces atleast 100-200 spikes , all of which pass through the stabilizer with out any resistance in to the equipment damaging it little by little. Equipment gets damaged over a period of 4-5 years. Spikes have duration in microseconds and stabilizer cannot react in such a short interval.

Our solution:

The solution we offered was in 2 steps.

1. Equipower- Main line Voltage protector with 20kA spike protection

We offered a 100A Equipower with single phasing preventor for complete premises so that it can handle problem of neutral opn or double phasing. In case of extreme over voltage it will cut off in fraction of seconds thereby saving the equipment from over voltage situation caused by external situations. It also has in built spike protection which prevents external spike from coming into the factory premises. Since there are other factory galas in the industrial estate, there is possiblity of spikes from other premises coming into the factory. So an Equipower at the main incomer helps in solving both of these issues.

2. Spike protection for individual machines

Each individual machine itself generates a spikes of its own and that is experience by other machines. There were several lathe machines and some CNC machines in the factory. Since the CNC machines were critical in nature we placed spike protection units at the individual CNC machines so that spikes from other machine do not enter in the CNC machine and damage the electronic PCBs over time.

3 Solutions for MOV damage problem in Solar inverter

Recently we visited a site where the solar inverter was damaged for third time. Both solar EPC as well as the client were distraught as all remedies had not worked and the solar inverter was damaged again. This is a common complaint by Solar EPC as well as the customers who have got solar power plant installed.

The response by Solar inverter companies was evasive and pointed out to things that are inconsequential and problem repeats after some days or months.

Many solar companies question the make of SPDs, ask for another make of SPD to be installed or ask to have another set of SPDs to be installed. They talk about grounding issues and connection problems. In one of those sites they recommended type 1+2 or class B+C surge protection, but that is something that should have been in place in the first place as the Type 1 responds to lightning impulses and type 2 is not meant for lightning protection. A normal ACDB does not have type 1 surge protection meant for lightning protection.

Root cause of problems -MOV damage

In all the occasions , MOVs ( Metal Oxide Varistors) are damaged. MOVs do not get damaged due to spikes , they merely stop conducting the spikes under normal conditions. MOVs burst is caused by over voltage and is not desirable as it damages the complete circuit and creates an internal short circuit. MOV damage will lead to downtime and brreakdown of machinery which in no way can be termed as voltage protection

If you look in picture above, the MOV rating is 420V and supply voltage is 415V. The voltage recordings for 48 hours revealed that phase voltage reached peak of 460V which is equivalent of 265V in single phase. This happened multiple times in 48 hours and also remained for considerable time – 15-20 mins each time.

SPDs and MOVs respond to spike only. They do not respond to continuous over voltage. If the continuous over voltage is beyond its threshold, like in the case above, the MOV will burst causing breakdown of solar plant.

Our solution for this problem

Our solution was offered as 3 options.

Option 1: Go for inverter with better specification

When we say better specification, we meant with internal MOVs rated for 500V and higher. This is however a bit difficult as the solar inverter companies would normally not disclose this information. Most Solar inverters are white labelled products manufactured in China. So it will also be difficult for them to change the specifications. Also one more problem is about neutral open or double phasing problem that happen on site. In all such situation even 500V MOV would get damaged.

Option 2: Complain to (DISCOM) authorities in documented form

In this option one has to file a written complaint to the DISCOMs and get an inward stamp. Anything that is documented needs to be closed. If not it is a big problem for concerned department. Verbal complaints over the phone are not entertained.

Did you know that as per Indian Electricity rules 1956 the supply voltage should not exceed 6% under normal and 12.5% under extreme situation? Did you know that you could use this as reference and make a big case if you had voltage recordings which proved that voltage exceeded 6%? The DISCOM would be deemed liable for the damages caused by this problem and would be held accountable.

The problem with this option is that it will involve courts and matter could takes months and years to resolve. But considering that you have some strong point here, one can and should take this option

Option 3: Go for voltage protection for solar inverter

This option is the most simplest and no brainer actually. Go for voltage protector with 10% cut off setting. In this case we have our product – Power kavach which can be offered with high voltage setting of 255V on higher side.

Only limitation to be taken in to account is that there will be a generation loss when the Power kavach shuts off the supply in case of over voltage.

There is always limit to courtesy extended by solar inverter or solar EPC. Free service and free replacements cannot be done indefinitely. It is always better to protect your equipment from such problems by using Power kavach

Have you faced similar problems ? Talk to us on 9769996205 or email on

Equipower installed at Brigade Cosmopolis, White Field, Bangalore by one of our dealers

This is a home voltage protector installed Brigade Cosmopolis, White Field, for voltage protection of complete home. Installation done by our dealer from banglore, cyneric technolgies

See the list of dealers in your areas

Equipower will protect against neutral open, double phasing, double voltage , 440V in any individual phase for more than 24 hours. It is designed for this purpose specifically.

#Equipower™ is a voltage protector which is connect in your main line and it protects all equipments connected through it. It can easily protect your equipment from voltage as high as 440V in single phase and that is what makes it special
It also  acts as an insurance against power fluctuation that could damage your electrical appliances and electronic devices used in your homes and offices .

#Equipower™ protects your electrical appliances and electronic devices against high voltage, low voltage, surges, spikes.  However what sets it apart from other protection devices is the ability to protect your equipment in case of #neutralopen and #doublephasing problems.  

Most of Equipments deteriorate very quickly after the warranty period. #Equipower™ increases life of equipments and minimizes the risk of damage.

for queries, you contact us on 9769996205 or fill the form below

How can OVCD substitute a stabilizer???

In most cases where a comprehensive solution for Power problem is required for any equipment  Let us take an example  of  ATM or any banking requirement.

Generally a combination power protection architecture is a as per below:

Isolation transformer + Servo Stabilizer + Online UPS system Your Appln

All of the above equipments are used to solve different aspects of power problem. Let see them one by one.

Isolation transformer:

  • An isolation transformer is a 1:1 (under load) power transformer used for safety.
  • Without it, exposed live metal in the equipment at a hazardous voltage relative to grounded objects
  • Electrical isolation is considered to be particularly important on medical equipment, and special standards apply. Often the system must additionally be designed so that fault conditions do not interrupt power, but generate a warning.
  • Isolation transformers are also used for the power supply of devices not at ground potential.
  • Designed to block interference caused by ground loops

Servo Stabilizer

  •  Designed to automatically maintain a constant voltage level.

Online UPS system

  • Meant for  emergency power backup  incase of power failure.
  • Provides a stable power Supply.

Seems like a foolproof protection system. However in spite of all this there are issues where equipment get damaged. Servo Stabilizer itself gets damaged. Online UPS gets damaged.  There are issues of Down time and service calls for both.



Double function – a waste

An online UPS is double conversion UPS, meaning that it converts AC –DC (Rectifier charger circuit) and DC to AC (inverter Circuit). So the output of Online UPS is stable irrespective of supply side fluctuations.

It has inbuilt AVR(Automatic Voltage Regulator) system which works as a Stabilizer circuit. It too has operating range like servo Stabilizer 150V-270V. Maximum may be 300V. After this the circuits start malfunctioning. UPS will function properly in this range and will not require a stabilizer.

So essentially Servo stabilizer before an Online UPS is big waste as it does not really protect the Online UPS and UPS will in fact does a better job at stabilizing the voltage levels than a servo Stabilizer.

OVCD – Powerful Alternative

How it works:

  • OVCD is connected at before the equipment in use. Incoming current will first pass through OVCD then into the equipment. OVCD continuously monitors the line voltage.
  • Whenever the voltage is above or below the set voltage limits the OVCD simply cuts the voltage to the equipment thereby saving it from the line disturbance.
  • OVCD will withstand the voltage even as high as 440Volts in single phase . Most equipments get burnt or damaged at this voltage but not OVCD.
  • It however does not stabilize the voltage as in the case of other devices in the same category like Stabilizer, CVTs.
  • When the voltage returns to normal , the OVCD resumes the supply to the equipment automatically with short power-on delay of 3 seconds(configurable). This feature is called the Smart Start. It prevents the initial harmful transient that may damage the Equipment.

How is OVCD better than Stabilizers?

  • Superior protection
  • Occupies less space
  • Lightweight
  • Transformer less design
  • Portable.


Comparison with Stabilizer

Protection up to 440V Yes No
Under voltage / Over voltage protection Yes optional
Protection from spikes Yes No
Lightweight Yes No
Waveform distortion Nil Nil
Response Time Less than 300ms 3 secs
Maintenance Not required Required

Cost comparison.

OVCD is 40% cost effective than any given stabilizer rating.

No price variations on wide range operations. Settings can be custom made.


Why should you consider using OVCD before your equipment?

  • Protection against Extreme over voltage.
  • No problems due to voltage fluctuation.
  • Zero downtime
  • Your equipment becomes more rugged
  • Less service calls = Increased profitability + Increased credibility.
  • Better perception of quality of your system in the minds of the customers
  • Increases the chances of repeat sales or referral sales.


Now you can install your equipment in the worst electrical conditions without being bothered about service calls.


Our proposed solution

Isolation transformer + OVCD + Online UPS system Your Appln

Why trust us on this solution

  • 15 years of experience in this domain.
  • Over 3.5 lakh live installations all across the country and counting
  • Solution is accepted by many UPS manufacturers like Emerson, Delta, Numeric, Techser, Eaton, GE and many more.
  • We have reduced their service issues related to power problems by more than 75%

Write to us for more queries on queries@microsystemservices.

Also see

1. Does an AVR or surge (spike) suppressor really protect from voltage fluctuations???

2. How  does Servo Stabilizer work?


About the Author (Click on the image to visit his LinkedIn profile)

Amit Manjrekar
Owner at Micro System Services

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