Hydrometer reading

I have bought a Hydrometer with AGS GX200F battery as well to check the gravity of the battery...according to info on net and battery sellers the gravity of a charged battery should be 12.5 but when Homage UPS stops charging and show UPS in full charge i check all the six lids and it gives me variable reading like 12.00 and 11.5 and 11??? is my battery ok ..i discussed that with the battery seller he told me that apply full load on UPS and check back up time when i did so ( it wasnt a full load as there is no need of fans in this season, only my desktop( core i 3 with a mid range graphics card and and 20 inch LCD) the inverter showed 2 bar load means = or < 50%(my inverter 1 KVA) it gave me 4 hour backup and still backup was working and battery mode showed 2 bars...now please share your knowledge with me...and my pc has a cooler master PSU 500 watts and intially it didnt used to restart while transfering to battery mode but now it started rebooting and restarting, is PSU harmed by modified sine wave output of homage inverter

no body have no idea about specific gravity??? and its effect on battery

Specific gravity is ratio of the weight of a solution (Sulphuric Acid in this case) to the weight of equal volume of water at a specified temperature.

For a fully discharged battery, the Specific Gravity is near to 1 and for a fully charged battery, it should be 1.25-1.28

lead-acid-battery-specific-gravity-charge-level.png

You can have a battery filled with specific gravity of 1.32 which will give you increased AH but at the expense of shortened life. So the choice of having a certain value of specific gravity is actually application dependent. For standby UPS, it is usually 1.25 and for battery operated fork lifters or traction applications, it is kept at 1.285

Specific gravity varies with temperature and the amount of electrolyte in a particular cell. But generally all the cells should give near same value.

1) Check if you have same level of electrolyte in each cell ? This difference could also come from by adding water to few cells (not all) and those cells would show less specific gravity even after fully charged.

2) How old is the battery ? You might have unequal degradation of cells in case of old battery thus you are having difference in specific gravity.

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and my pc has a cooler master PSU 500 watts and intially it didnt used to restart while transfering to battery mode but now it started rebooting and restarting, is PSU harmed by modified sine wave output of homage inverter
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Either your UPS switching over time increased a little (might be due to weak battery) or the electrolytic capacitors inside your power supply of the CPU have degraded.

Modified sine wave does not harm the PSU of computer but the spikes do harm it.

Thankyou Ijaz...but my battery is new and its giving good backup as well...but each cell show diff specific gravity reading in full charged battery as well...one or two cell show only 1.2 other are lower than 1.2??? what do u think about this situation...my hydrometer is new as well i bought it for 200 rs

i think that there is no problem with your ups

when your battery is full charged converter cut off with battery

converter is always convert the ac supply into dc supply