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Lead Acid BAttery

Lead Acid BAttery

Lead Acid BAttery

(OP)
hi...i just want ask some signs of battery failures...such as grounded plates, etc...we have a 1250KVA Generating set, the unit is about 2year old...But recently it had a problem during start-up...it doesn't start as quickly as compared last week...then we noticed that its battery(2-12Volts, 27PLates Battery) were humming during charging period...is it a sign that the battery plates were grounded..???...  

RE: Lead Acid BAttery

Half the plates in one cell _should_ be grounded.  The remainder could be grounded only if the case is breached, which is uncommon.  

More likely; some cells are low on water and/or the terminals are corroded.

Have the battery serviced by a qualified technician.





 

Mike Halloran
Pembroke Pines, FL, USA

RE: Lead Acid BAttery

quote from above... "but a proper well made standby battery will last 20 years or more. The ones used in subs last for a decade or so"

Ditto...

10 year design life http://www.eastpenn-deka.com/assets/base/0965.pdf

20 year design life  http://www.industrialenergy.exide.com/products/range_select.asp?range=GP&sub_id=17&lng=en&cl=np_brands

In our business we design, install DC Power Plants and currently are maintaining close to 75 sites on contract using the above 10 and 20 year life batteries..

Properly maintained (and there's more to this than most assume) they can reach their design life.  Compliance with manufacturers charge voltage to ambient temperature curves is the most important factor for long life. Recent studies and white papers by the manufacturers of AGM VRLA batteries point out that these batteries have a fairly narrow tolerance in this regard.

Air conditioned space with constant ambient temperature and, low humidity also helps minimize any chance of external terminal/strap corrosion.

They should never be exposed to operating conditions higher than 95 deg F to avoid the risk of thermal runaway, which will destroy the batteries.. Have 2 sites where this has occurred due to lack of maintenance/failure on air conditioning systems.    

RE: Lead Acid BAttery

Wish this site had edit capability..

Obviously your generator environment can't be as well controlled as implied in my post above. but charge voltage to average ambient might be something you want to look at.

Wet cell batteries are much more tolerant with regard to temperature, but require more maintenance to control corrosion.

RE: Lead Acid BAttery

You can red flag your post and offer a replacement post with the edit.  

RE: Lead Acid BAttery

On a lead-acid battery, neither set of plates should be grounded unless it is installed in a system that grounds one side, as in most automotive and generator starting systems.

Starting batteries often have a rough life.  Our company SOP calls for replacement every three years unless problems surface earlier.  Trying to push past three years is asking for trouble.

I agree that flooded-cell lead-acid batteries in many services can last ten-twenty years with proper care, but that's a different game.

Following a start attempt, it is not unusual for the battery to make some heat as it recharges.  It should not "hum" unless the charger is introducing an AC component into the charging circuit.

One problem not uncommonly found with starting battery sets is that some manufacturers aren't reluctant to sell a multiple million dollar generator installation and then install a cheesy battery charger along with it.  

Refer to battery manufacturer literature for the proper charging parameters and make sure your charger is supplying proper voltage and that it is reasonably free of ripple.  If the voltage is wrong and cannot be adjusted, consider installing a better battery charger.

old field guy

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