battery testing

Battery testing practical

for this practical, a 12 volt battery, digital multimeter, hydrometer, high rate discharge tester (load tester), digital battery tester, safety glasses, safety equipment were required.

The battery used was a Champion 126HD with 310CCA. First thing I did was a visual inspection of the battery terminals and leads for any corrosion or any leakage. Found none
• next I did a visual check of the electrolyte levels and they were okay.
  
  
• next was an open circuit voltage test. before this test I removed surface charge,turning on the lights for a minute to do so. In the volts DC unit on the multimeter the batterys charge was 11.50 V which is less than 50% charged required to continue testing
  
  
• a specific gravity test was next. This required the use of a hydrometer, inserting it the cell's electrolytes.i wore safety glasses a safety precaution. With the hydrometer inserted in the cell, squeeze the rubber top of it and release to allow just enough water to make the floating indicator float. The reading is taken at level for a precision. 
  the specifications and the results table are listed below 
  
  

  
  1.240 – 1.260 = 100% Charged

  1.210 – 1.240 = 75% Charged

  1.180 – 1.210 = 50 % Charged

   1.150 – 1.180 = 25 % Charged
  
  

  Cell	1	2	3	4	5	6
  Reading	-	1300	1275	-	1280	-
  Colour		murky	murky		murky

  
  
  This battery failed the specific gravity test and the open circuit voltage test so I couldnt use it further
  
  
  To continue the High Rate Discharge Test I then used another battery AA brand with a 330CCA
  Required for this test was a load tester which I would apply a current that half of the battery's cca, i.e 165CCA.:
  Connecting the load tester to the battery terminals positive first,i applied the load,holding it for 20 seconds to get a reading : 11.44 V held the battery passed the test. the result of this test indicate
  the current that is used when the car is switched off.
  
  
  next a parasitic draw test,which requires me to test the battery in series with a digital ammeter.
  The amp draw was 0.02A which was a pass(specification 0.02A-0.05A)
  
  
  Then I used a digital meter test . This is powered by the battery being tested so a failed or very low voltage battery would not be suitable for this test. The battery voltage should appear in this case it was an OCV of 12.68 V. Scrolling up or down with the arrows on the meter, select to put the batterys CCA (330) and select test. Pass indicates a good battery..Ch to charge it or Fail which means that.My result was pass.
  
  
  the above test showed the battery was in good condition and I still use it in my car even today