VI ELECTRICAL 3 9 S ll lllscliarg llala Gliarl uua A l a n t f Dlsvlurur F v v olsREcARD ru Fam nn nay SUGHT 1oo i 37 B Cl 09025 speeme orsvny BARREL 9 CURVATURE so 2s 1 cl 0 0010 specme Gravity n o vr E I 50 i uo c 0 0002 specane Gravity I am 5 In rare cases where a battery goes dead and no A apparent cause can be found the battery should be rnsnmomzrsn fully charged and allowed to stand on a shelf for three to seven days to determine if self discharge is exces sive The Self Discharge Rate Chart shows allowable self discharge for the first ten days of standing after a Mn 43 battery has been fully charged A fully charged bat tery is a battery which does not increase the electro Fll 3 4 v r t r M l W Ml l m ll l lyte specific gravity after three continuous hours of charging Temperature corrected specific gravity equals 1 240 minus 0 0 equals 1 212 A fully charged battery should have a specific grav l w rMn 1 r Tos ity or 1 250 to 1 265 lf the specific gravity of all cells is above 1 235 d Pump tg w tmg vlslmlly mspwi the battery for in 1 196 tropical climate but the variation between cells amage m en commnen cover se DWL ew t 3 is more than 50 points 0 050 it is an indication of an would make the battery uns rv bl The t unserviceable battery and the unit should be removed method of reading a hydrometer is to have the liquid from the car fu furth r testing in the hydrometer at eye level fig 3 4 Disrcgard the curvature of the liquid where the surface rises against 4 the float due to surface tension Draw only enough liq I g ge2hfi Z1 id2 L z g iimw battery will uid in to keep the float off the bottom of the barrel The hydrometer must be kept vertical while drawing If the specific gravity of one or more cells is less in liquid and taking the reading Care should be than 1 235 recharge the battery at approximately 5 taken when inserting the tip of the hydrometer inw amperes until three consecutive hourly readings are the cell to avoid damage to separators Broken constant separators could result in premature battery failure At the end of the charge period if the cell variation Hydrometer floats are generally calibrated to indi is more than 50 points 0 050 replace the battery cate correctly only at one fixed temperature 80 F When the specific gravity of all cells is above 1 235 The temperature correction amounts to approximately and variation between cells is less than 50 points the 0 004 specific gravity referred to as 4 points of grav battery may be tested under load ity For each 10 F above 90 F subtract 4 points Always correct the readings for temperature variation Test the specific gravity of the electrolyte in mh bat SPWIHU GNVIW lliidllll tery cell Example A battery is tested at 10 F and has a specific gravity of 1 240 The actual specific gravity is found as follows Sm 1 M Tun Number of ab0ve or below 80 F equals nh l 70 80 minus 10 degrees 70 divided by 10 each 10 degree difference equals Fully charged 1 265 7 75 cnargen 225 7 x 0 004 temperature correction factor equals 50 gmqsd 1 1go 0 028 25 Charged 1 155 Temperature is below 80 F so temperaturee correc Disdmm M20 tion is subtracted 60340