Voltage variation is a common phenomenon. In India, all electrical equipment are designed for 230 / 400 volts single / three phase. If the voltage maintained ± 5% then that is tolerable & does not effect on performance/ life of the equipment. The Input voltage is generally low during the day time and high during the night hours. Apart from this, a few months in a year or a few days in a month or a few hours in a day – the voltage is either low or high due to the following reasons:
- Holidays
- Weather Conditions
- Agricultural Load
- Rainy days
- Peak Hours
Effects of High Voltage: The high Voltage no load current of electrical or electronic equipment increases sharply. This high current increases the losses of equipment resulting overheating, weakens the insulation of electrical or electronic equipment and becomes the cause of pre-mature failure of electrical or electronic equipment as explained in the next table:
Effects of Low Voltage: The low voltage does not increase the no load current. In case of very low voltage, the equipment does not work or operate, which results in production loss or uneven quality products. To run the unit in case of low voltage, it needs an alternative source of power, i.e., DG power supply which is very costly and not reliable.
Earlier no reliable technology or manufacturer were available in India – due to that customers installed the A VC on every individual machine, which has lot of deficiencies like higher power consumption, non- availability of servicing in case of any problem – and ultimately became scrap for the company.
In the year I 990, we developed the linear voltage regulator contact assembly up to 3000 kVA, which is quite reliable or dependable with lesser losses. This has a working life of I 0-15 years and recovers the invested money within 6 to 18 months, i.e., depending on their voltage variations. Where the voltage is higher its payback is too short, i.e., 6 to 12 months.
Post Sales Service: It is the most important part after the sale of any equipment; we have more than 10000 installations in pan-India with service structure, i.e., located in every major cities of every state of India. To maintain service structure throughout India for prompt service after sales costs to company on an average 25-30% of the equipment.
Bypass: A VC is an electro-mechanical machine and is having lot of moving mechanical parts. There may be fault any time, which may be 1 out of 100 products, to avoid any production loss or run trouble-free – you can bypass the Automatic Voltage Controller till the time the service engineer reaches the site and rectifies the problem. It is only 20 to 25% cost of the equipment.
So, the power consumers having high failure rate of electrical equipment, higher MDI, can reduce the failure rate of equipment & MDI by maintaining their voltage at 400/415 V.
Conclusion: If they find voltage fluctuations, then they check their voltage hourly in a day for a week, accordingly they should rectify the problem through installed Automatic Voltage Controllers.
B. Jindal
The author is the Founder of Jindal Electric & Machinery Corp. He may be contacted through e-mail: jemc@jindalelectric.com
