Xantrex Technology 815-2524-02 User Manual

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Freedom SW 230V Installation Guide
Stacking Features
each parallel branch of batteries. Therefore, the above 
generalizations of maximum charge rate (%) can be made for the 
entire battery bank.
The Freedom SW 230V’s Max Chg Rate (%) setting defaults to 
100
 (adjustable from 0 to 100). So if the Freedom SW 3524-230 
charger with a maximum possible 90A charger capacity is set to a 
Max Chg Rate
 of 100 (%) then its full 90A of current can be 
delivered into the battery bank. However, if this is too high, the 
installer/operator may reduce the Max Chg Rate setting to suit the 
system battery type and bank requirements (and limitations), to 
avoid overheating the battery bank. 
The user/installer is responsible of configuring the charger to ensure 
that the battery manufacturer’s recommended maximum charge 
rate current 
(in Amps) is not exceeded to prolong battery life and 
to exhibit best performance.
Examples
Example 1:
System composed of two stacked Freedom SW 2524-
230s. Each Freedom SW 2524-230 has a maximum charge capacity 
of 65A.
The industry’s commonly accepted practice suggests a typical 
Flooded battery bank capacity (C) of 400Ah should not be charged 
beyond 25% of its capacity (100A). Therefore, when configuring the 
two stacked Freedom SW chargers, each charger may have a 
maximum allowable charger output current of 50A (400 × 25% × 
1
/
2
into the common battery bank as described in the Calculations 
section. Also, the System Total BULK output current is calculated 
as 100A (50A + 50A).
To set the Max Chg Rate (%) setting in each Freedom SW 2524-230:
1.
Divide the maximum allowable charger output current of 50A 
by the Freedom SW 2524-230’s maximum charge capacity of 
65A.
So, 50 ÷ 65, gets an approximate value of 0.77 (or 77%) which 
can be roughly reduced to 75%.
2.
Set the Max Chg Rate (%) setting to 75 which means 75%.
In this example, the actual output current is limited to 75% of 65A 
which is 48A. Therefore, the actual System Total BULK output 
current
 comes out to just under 100A. 
Freedom SW 3K2K 230V InvChg Install Guide.book  Page 48  Friday, June 20, 2014  9:11 AM