02-17-2011 09:39 AM
In my experience the most common cause of a "starting battery" explosion is low fluid levels causing the plates to be exposed to the combustible atmosphere inside the cell/s affected. On mobile equipment the most usual cause is slight overcharging causing the
fluid to boil off combined with lack of electrical system maintenance. In a Genset aplication the most likley cause is loss of fluid due to constant
chargeing in a high ambient temperature environment such as is found around most genset engines.
Hope this helps.
02-17-2011 04:40 AM
It is possible that the electrolyte level in the bttery was low , maybe on only one cell and this produced a short circuit across the plates which in turn ignited the hydrogen gas ....I had a similar fault on a battery when I was working in the Seychelles where we ran a lot of gensets to supply power to the islands resorts ..we moved over to gel batteries...
02-01-2011 05:57 PM
Hard to suggest since no failure mode is identified with a cause. Id suggest the maintenance free batteries from CAT if your interested. Most battery issues Ive seen are from faulty chargers, having charger set incorrectly, or lack of cleaning around the terminals such.
03-08-2010 12:26 PM
The history of arc flash started with the electric utility industry in the 1980's. By 1994 OSHA had put in place 1910.269 requiring utilities to not allow clothing which "could increase the extent of the injury" in the event of an arc flash. Coupled with the 1910.335 requirements for face protection in the event of an electrical explosion, many of us in the utility industry began researching options for arc flash clothing and PPE. In the early 1990's ASTM's F18 committee for electrical protective equipment developed test standards which were later incorporated into NFPA 70E. In early 1999, some of us formed IEEE 1584 and relied on limited donations of a very few companies (ours included) to do some arc flash testing to add to the data we had amassed for about 15 years through the ASTM committee. I do most of the arc flash testing at www.arcwear.com on clothing through the Kinectrics lab in Toronto but some is done through our IEC 61482 method at labs in Russia, Switzerland and in Canada.
Actually NFPA put arc flash calculations in the 1995 version and clothing entered in 2000. The 2004 and 2009 versions have added much clearer guidance and we have many improvements coming for the 2012 version in process right now. There was no NFPA 2002 version but IEEE 1584's latest version is 2002 but a large study is going on right now to update this substantially. We use IEEE 1584 (embedded in almost all software) for calculations up to 480V and we also use ArcPro software beyond 480V as a double check since IEEE 1584 tends to over predict the energy the higher the voltage goes.
The NFPA 70E tables are very limited and rarely can officially be used BUT they have saved many lives. Dr. Tom Neal, Dan Doan and I have a paper presented at the IEEE-ESW which explores 40 incidents in which the tables fully protected the workers in almost every case. Don't put off training or PPE waiting for arc flash studies BUT the studies can help reduce injuries and exposures.
I recommend having a PE review all flash studies because we've seen many companies enter this in the last few years who use software to do the studies but don't really understand what is needed to do a real fault current & coordination study properly and they end up with outlandishly high calorie ratings or extremely low ratings. It is often a function of not taking all factors into consideration. Many flash studies are very simple to do. The most costly portion is data gathering and most of our customers do these themselves with a local contractor and have a PE review the information after the model is build. We recommend doing flash studies in-house if you can since the NFPA standard and good engineering practice requires review of the study on a 5 year basis and keeping it up to date. Doing a study has many advantages.
For more info see my article on American Chronicle.
Sr. Managing Partner