EEE World, Department of EEE, ADBU: Selection of Various Types of Inverter-(Part-2)

Comparison of Inverters:

Comparison of Different Type of Inverter
	Square Wave	Stepped Sine Wave	Pure Sine Wave
Safety of Appliances	Less	Moderate	High
Life of Appliances	Less	Moderate	High
Battery Life	Less	Moderate	High
Noise Level	High	Moderate	Normal
Heat generation	High	Low	Normal
Suitability for appliances	No	Not recommended for prolonged use	Yes

Batter is the vital part of inverter. Performance and life of an inverter is greatly depends upon battery.
There are three types of batteries available in market.

Without getting too much into details, all we can say is that Tubular Batteries are the best choice for inverters. They may cost slightly more than Flat Plate, but they will last longer.
Maintenance Free batteries may sound good, but they have lesser life (4-5 years as compared to 7-8 years of a tubular battery).
But the most important thing to run batteries for a longer time is to make sure that it is topped (filled) with distilled or RO water frequently and the fluid levels are maintained.

Lead acid batteries known as “Automotive Battery”.
Lead-acid batteries are the oldest type of rechargeable battery. Most of the inverters batteries are lead acids battery of different types.
It is used for automotive purpose are termed as “High Cycle” lead acid batteries.
These batteries are designed to provide high current for a very short duration (To start the vehicles).

Automotive lead acid batteries are not designed to be regularly discharged by more than 25% of their rated capacity. Here the requirement of inverter is totally different.
Inverter requires “Deep Cycle” type batteries to provide continuous power which can be discharged at least 50% of their rated capacity.
Some good deep cycle batteries can be discharged over 80% of their capacity. Deep Cycle batteries have specially designed thick plates to withstand frequent charging and discharging.
Lead acid batteries require regular maintenance. You have to check the electrolyte level and require to be topped up on regular intervals. These batteries release poisonous gases during charging and discharging. If you don’t keep the batteries in a properly ventilated place, it can invite serious health problems.
We have to keep the terminals of normal lead acid batteries corrosion free by applying petroleum jelly or grease regularly.

Advantage:

Disadvantage:

We need maintain it regularly, such checking the electrolyte level, topping up with distilled water etc.
Need well-ventilated place while installing a lead acid inverter battery.
Not Safer in use.

Application:

This is the most popular and efficient among all types of inverter batteries.
Together with robust grid design, superb efficiency, long operational life and requirement of low maintenance tubular inverter battery is the most preferable choice of all.

This is the most popular segment of inverter batteries used in domestic and industrial applications.

Advantage:

Disadvantage:

Application:

As the name indicates there is no need of maintaining the batteries. No need of filling distilled water at regular intervals. This is possible because of a special type of electrolyte which need not be replenished.
Maintenance free batteries also called as sealed batteries and do not need any regular maintenance to function impeccably.
Apart from that other best feature is safety. Maintenance free batteries do not emit any poisonous or harmful gases.

Advantage:

It is costlier, But the money is worth to invest.
It is sealed lead acid batteries which do not require topping up or additional ventilation
They are more durable and safer than normal lead acid inverter battery.

Disadvantage:

Application:

Comparison of various types of Batteries
	Flat Plate Batteries	Tubular Batteries	Maintenance Free Batteries

Cost	Low	High	High
Safety	Low	Low	High
Efficiency	Low	High	Medium
Maintenance	High	Medium	Low
Water toppings	High	Medium	Low
Releases harmful gases	Yes	Yes	No
Ventilation requirement	Yes	Yes	No
Scrap Value	High	High	Low
Weight	Low	High	Depend on the model.
Battery Life Span	Low ( 3 Yrs)	High( 5 Yrs)	Medium (3 to 4 Yrs)
Suitable	For Low power cut areas as their designed cycle life is low.