Xantrex Technology 815-2524-02 User Manual
975-0697-01-01
47
Stacking Features
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Charger Settings in a Dual Freedom SW Configuration
The Freedom SW 3524-230 includes a maximum 90A charger.
When using two stacked Freedom SW 3524-230 inverter/chargers
connected to the same battery bank, a total of 180A (90A × 2) of
bulk charging is possible into that single common battery bank. For
small battery banks and/or certain battery types this bulk mode
current may be too high, therefore Freedom SW 230V models
include a battery bank capacity (Batt Capacity) setting and a
maximum charge rate (%) (Max Chg Rate) setting.
When using two stacked Freedom SW 3524-230 inverter/chargers
connected to the same battery bank, a total of 180A (90A × 2) of
bulk charging is possible into that single common battery bank. For
small battery banks and/or certain battery types this bulk mode
current may be too high, therefore Freedom SW 230V models
include a battery bank capacity (Batt Capacity) setting and a
maximum charge rate (%) (Max Chg Rate) setting.
The battery bank capacity (C) is the bank’s total Amp-hour capacity,
which is best determined by a qualified RV electrical technician.
which is best determined by a qualified RV electrical technician.
The Max Chg Rate depends on the battery manufacturer's
maximum charge rate for the specific battery model being used to
construct the bank. This total bank maximum charge rate is best
determined by a qualified RV electrical technician. Suitable battery
types include Flooded, GEL and AGM. Do not mix different battery
types within the same battery bank.
maximum charge rate for the specific battery model being used to
construct the bank. This total bank maximum charge rate is best
determined by a qualified RV electrical technician. Suitable battery
types include Flooded, GEL and AGM. Do not mix different battery
types within the same battery bank.
For a Flooded type battery bank, the preferred charge rate (in Amps)
is usually 10-15% of C where C = battery bank’s total Amp-hour
capacity. However, the industry-accepted maximum charge rate is
25% of C. Some AGM or Gel battery models may have a maximum
charge rate as high as 50% of C and in rare cases, up to 100% of C.
is usually 10-15% of C where C = battery bank’s total Amp-hour
capacity. However, the industry-accepted maximum charge rate is
25% of C. Some AGM or Gel battery models may have a maximum
charge rate as high as 50% of C and in rare cases, up to 100% of C.
Do not exceed the battery manufacturer’s recommended maximum
charge specifications because the resulting battery temperature rise
shortens battery life.
charge specifications because the resulting battery temperature rise
shortens battery life.
Calculations
Once installed and configured, each Freedom SW 230V charger in
the dual configuration should be set to its own bulk charge current
limit as follows:
the dual configuration should be set to its own bulk charge current
limit as follows:
Industry accepted maximum charge rate (%)
× battery bank’s total Amp-hour capacity (C)
×
1
/
2
(for one of the chargers)
= Maximum charger #1 output current (in Amps)
allowed in bulk mode (also limited to the charger’s
maximum capacity)
maximum capacity)
To calculate the system total bulk output for the stacked pair,
Charger #1 output current (in Amps)
+ Charger #2 Actual output current (in Amps)
= System Total BULK output current (in Amps)
= System Total BULK output current (in Amps)
The System Total BULK output current flows into the battery
bank. As such, this total bulk current is split/distributed within the
bank through each individual parallel and/or series connected
battery. Therefore, the current each battery “sees” must not exceed
each individual battery’s maximum allowed charge current as
specified by the battery manufacturer. Since most battery banks are
comprised of the same battery type, model and length of
interconnecting cables, current sharing is roughly equal through
bank. As such, this total bulk current is split/distributed within the
bank through each individual parallel and/or series connected
battery. Therefore, the current each battery “sees” must not exceed
each individual battery’s maximum allowed charge current as
specified by the battery manufacturer. Since most battery banks are
comprised of the same battery type, model and length of
interconnecting cables, current sharing is roughly equal through
Freedom SW 3K2K 230V InvChg Install Guide.book Page 47 Friday, June 20, 2014 9:11 AM