steven Posted April 6, 2009 Author Report Posted April 6, 2009 ive missread the details on my 12 volts sealed lead acid cell batterys they are 7.0 amps at 12 volts not 2.1 amps , today i got a higher current battery 9.0 amps and are testing it on my hho circiuts Quote
audioguru Posted April 6, 2009 Report Posted April 6, 2009 Hi Steven,Are your batteries rated at 7A and 9A or at 7Ah and 9Ah?Ah is ampere hours.According to The Battery University on the internet, a SLA battery rated at 9Ah can supply 0.45A for 20 hours or 1.8A for 5 hours. It might not be able to provide 9A. Quote
steven Posted April 7, 2009 Author Report Posted April 7, 2009 i have 7 amp and hopur 12 volts and 7.2 amp an hour 12 volts and just got a 9 amp an hour 12 volts seald lead acid cell battery , ive allways had trouble working out the details of what current they really was as there was some details on the sides i wasent sure of Quote
steven Posted April 7, 2009 Author Report Posted April 7, 2009 :)cant get them all into this picture but here they are Quote
audioguru Posted April 7, 2009 Report Posted April 7, 2009 The batteries say, "Do not short circuit" but you did with your current meter.The little one says, "7Ah at 20 hour rate", not 7A. It can supply 0.35A for 20 hours. Its max allowed charging current is 2.1A.The larger one says, "9Ah", not 9A. It does not say at what current. Its max allowed charging current is 2.7A. Quote
steven Posted June 25, 2010 Author Report Posted June 25, 2010 :) dispite what they all say about useing steell wool as a flashback arestor then 0000 grade fine steel wool i have had many seccess with it note the pink flame and i had to film it then replay and pause it then snap the picture off my pc to upload to here. the colour of flame you can see in the picture filmed from a handy cam but not with the naked eye as its different then , i can instantly melt through high resistance wire nichrome wire and heat iron pyrite instantlt to red hot and melt it , and allso lead from a pencil and brass but not coper or nickle so the flame seems to be fusy at what it can melt and heat to red hot so most of what i can heat to red hot and melt are high melting piont metals mostly Quote
Hero999 Posted June 25, 2010 Report Posted June 25, 2010 If the short circuit current is only 9A then the batteries are flat and dead.I looked up the datasheet for one of the batteries you're using. It's 7.2Ah and the internal resistance is just 40mΩ when in good condition and fully charged. When fully charged to 13.8V, the short circuit current will be 345A and will quickly drop as it rapidly discharges. The large current will cause the meter's fuse to blow before anything bad happens.The capacity is 7.2Ah when the temperature is 25 Quote
steven Posted June 25, 2010 Author Report Posted June 25, 2010 :) my meters never blew and my batteries still run ok and i just top them up when i like to keep them charged so i wont use my battery power up when i use them longer i have no major problems at all regardlless of what you find about these batteries , Quote
Hero999 Posted June 25, 2010 Report Posted June 25, 2010 Then you obviously measured current in the correct manner by connecting the meter in series with the circuit. Quote
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