i recently installed APC ups 1500i. In bulk charge voltage gradually rises and reach to 27.73v and then absorption period starts in which voltage decrease to 27.61v with declining of current. when current reaches to approx 0.5-0.6a, i think this is the float charge in this stage the the voltage again rises to 27.71v.
now there are few points which i want to clear up.
1. on many websites they say that on bulk charge when it reached to set voltage then absorption stage starts with constant voltage, WHY DECREASE VOLTAGE FROM 27.73 TO 27.61. .
2. in float charge, the voltage must be lowered than absorption stage. WHY iNCREASE VOLTAGE FROM 27.61 TO 27.71
is there any problem in the charger of ups.
here is the picture also