Battery Maintenance

Battery Maintenance
To ensure the integrity of​ any Uninterruptible Power Supply, Telecommunications 48V system or​ generator, the lead acid batteries must be checked and​ maintained.
Surprisingly what ever the cost of​ your​ Power Protection​ system, whether it​ is​ a​ stand​ alone UPS System or​ Standby Diesel Generators the most common​ single point of​ failure are the batteries.
High resistance, leakage or​ open circuits will cause batteries to​ fail; no longer providing the expected autonomy or, in​ the case of​ a​ generator the inability to​ start .​
The Result - loss of​ the site load .​
Then suddenly you​ require a​ 24-7 emergency call out engineer.
Uninterruptible power supplies may have internal batteries or​ housed in​ separate battery cabinets .​
Each battery has a​ recommended design life, usually 5 years or​ 10 years, although these are optimistic as​ they don't take into account high usage of​ the UPS Battery system caused by intermittent spikes, brown outs or​ voltage fluctuations which are absorbed by the batteries to​ protect your​ mission​ critical sensitive systems.
Even though the battery may have an​ operating life expectancy stated by the manufacturer of​ typically up to​ ten years, if​ it​ is​ not checked on​ a​ regular basis it​ can and​ will fail .​
in​ a​ string of​ 32 blocs all it​ takes is​ one battery to​ become high impedance and​ the complete string will be useless as​ the load will be unable to​ draw the current it​ requires and​ as​ a​ result the load will be lost and​ your​ critical load will fall over .​
The old batteries can be removed and​ new batteries supplied.
The most obvious signs of​ Battery leakage due to​ failure within​ the sealed lead acid battery causing the casing to​ split can be visible .​
Other issues of​ high impedance and​ open circuit are not obvious and​ require regular checks.
There are a​ number of​ different types of​ battery construction​ but they can be loosely divided into to​ two common​ types-'wet cells' and​ 'valve regulated lead acid' (VRLA) batteries( often referred to​ as​ just ‘sealed lead acid batteries').
Wet cell battery maintenance can be more time consuming, as​ the trade off against increased life expectancy is​ the higher cost of​ maintenance due to​ the necessity of​ taking specific gravity readings and​ ‘topping' up the cell .​
a​ visual check of​ wet cell batteries needs to​ be undertaken on​ a​ more regular basis as​ any noticeable drop in​ electrolyte level must be swiftly rectified.
The VRLA 'lead acid' battery is​ more difficult to​ check being a​ sealed battery .​
The most common​ method of​ testing, often built into most UPS systems equipment is​ a​ battery self test which is​ often carried out automatically on​ a​ weekly/monthly time cycle .​
if​ the test fails the UPS system will generate an​ alarm .​
The major drawback is​ if​ the equipment is​ supporting a​ small load comparative to​ the capacity of​ the equipment the battery will not be worked very hard and​ could prematurely fail.
The more reliable means of​ regular testing a​ battery is​ either:-
1 .​
By loading the battery to​ one third of​ its capacity and​ carrying out a​ capacity test
2 .​
impedance testing -increasingly popular as​ it's non-intrusive.
There are several methods of​ achieving the same result but one method is​ to​ pass a​ known ac current through the battery and​ measure the ac voltage and​ thus, by using Ohms Law calculate the battery impedance .​
These results can be compared with the manufacturer's recommended value and​ by keeping records can be compared over a​ period of​ time allowing a​ replacement programme to​ be implemented when the battery impedance has reached a​ preset value.
Which ever method of​ battery testing you​ choose , regular battery maintenance is​ an​ integral part of​ any Uninterruptible Power Supply or​ Generator standby power protection​ system .
PowerContinuity Means Business Continuity
for​ further information​ regarding uninterruptible power supplies please visit our website at​

You Might Also Like:

Powered by Blogger.