Specifications
12 
Figure 4-2 shows the sequence of the stages. 
Figure 4-2 TRACER MPPT charging algorithm 
·Bulk Charge 
In this stage, the battery voltage has not yet reached boost voltage and 100% of 
available solar power is used to recharge the battery. 
·Boost Charge 
When  the  battery has recharged  to the  Boost  voltage  setpoint, constant-voltage 
regulation is used  to prevent heating and excessive battery gassing. The  Boost  stage 
remains 120 minutes and then goes to Float Charge 
·Float Charge 
After the Boost voltage stage, TEACER will  reduce the battery voltage to Float 
voltage setpoint. When the battery is fully recharged, there will be no more chemical 
reactions and all the charge current transmits into heat and gas at this time. Then the 
TRACER reduces the voltage to the floating stage, charging with a smaller voltage and 
current. It will reduce the temperature of battery and prevent the gassing, also charging 
the battery slightly at the same time. The purpose of Float stage is to offset the power 
consumption caused by self consumption and small loads in the whole system, while 
maintaining full battery storage capacity.   
In Float stage, loads can continue to draw power from the battery. In the event 
that the system load(s) exceed the solar charge current, the controller will no longer be 
able to maintain the battery at the Float setpoint. Should the battery voltage remains 
below the Boost  setpoint, the  controller will exit Float stage and return to Bulk 
charging. 










