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1.1.5  4100-0157A Battery Charger Faults 
 
There are a number of Battery Charger Faults that can arise during the operational lifetime of a panel.  You may 
observe one of the following Faults; 
   
    Charger 2% out of range 
    Battery Charger Supply incorrect 
 
The  most  common  cause  is  one  or  possibly  both  batteries  are  faulty.  Before  proceeding  to  adjust  the  power 
supply  as  described  below,  measure  the  voltage  of  each  battery  while  it  is  under  load.  Both  batteries  should 
measure within 0.1v of the other 
 
 To correctly measure the output voltage you will need to follow the steps below. 
 
1.  To prevent damage to the system, disconnect the batteries & power down the system, disconnect 
the power & comms harnesses from the Power Supply.  
 
2.  Connect the  Multimeter to  the battery leads (with batteries disconnected), power up  & measure 
the voltage. Calculate the difference between the measured voltage & 27.6v.  
 
NOTE:  After  90  seconds,  the  voltage  will  drop  to  <24v.  If  this  happens,  power  down  &  start 
again. 
 
3.  Connect the Multimeter to the A or B tap on TB2. Measure the voltage. Adjust the trim-pot (refer 
to the Trimpot Location diagram found on Page 22)  so the voltage increases (or decreases) by 
the difference calculated in step 1.