Installation and Operation Manual
4
Acceptance Charge
When the battery recovers sufficient charge for battery voltage to rise to the Acceptance Charge Voltage setpoint (factory set to 14.2/28.4V) current is
reduced as necessary to hold the battery at the Acceptance Voltage. The 1524 remains in Acceptance until the battery is fully charged as determined by either;
1.
The 1524 has remained in Acceptance continuously for the Charge Time period (factory set to 2 hours).
– OR –
2.
With the IPN-ProRemote display, net battery charge current while in Acceptance decreases to the Float Transition Current setting (factory
set to 1.5A per 100 amp-hours of battery capacity).
Float Charge
Once the battery is fully charged a somewhat lower Float Voltage (factory set to 13.2/26.4V) is applied to maintain the battery in a fully charged state
without excessive water loss. During Float a healthy fully charged lead-acid battery will draw
≈
0.1–0.2 amps per 100 amp-hours of battery capacity.
TWO STAGE CHARGE CONTROL
Certain battery types or system configurations may require two stage charge control which eliminates the Float charge stage. The 1524 can be configured
for two stage Bulk/Acceptance charge control by setting the Float charge voltage setting to No Float using the IPN-ProRemote. Refer to the IPN-ProRemote
operators manual.
FRONT PANEL INDICATORS
FIGURE 1
EQUALIZATION
¾
WARNING:
Not all batteries can be safely equalized. Equalization should be performed only on vented liquid electrolyte
lead-acid batteries. Always follow battery manufacturers recommendations pertaining to equalization. Equalization applies a
relatively high voltage producing significant battery gassing. Disconnect equipment that cannot tolerate the high equalization
voltage which is temperature compensated.
The SB1524 can perform automatic equalization alone, or manual equalization via the IPN-ProRemote. Equalization is essentially a controlled
overcharge which applies a relatively high voltage to bring all battery cells up to the same specific gravity and eliminates electrolyte stratification by heavily gassing
the battery. While equalization parameters are adjustable with the IPN-ProRemote, factory default parameters of 15.2V for 2 hours every 30 days are suitable for
most applications. A minimum net charge current of approximately 3.5 amps per 100 amp-hours of battery capacity is required for proper equalization.
The equalization timer is a “time at voltage” time accumulator counting in 3 minute increments. The equalization timer will not count down unless the battery
reaches the equalization voltage setpoint. Unless manually canceled the 1524 will stay in equalize for as long as necessary to accumulate the required time at
voltage. If equalize does not complete by end of the charging day it will resume where it left off the next charging day. If equalize does not complete in a reasonable
period of time due to insufficient current, it should be canceled manually via the IPN-ProRemote or by momentarily removing power to reboot the 1524.
CURRENT LIMIT
Automatic current limit prevents output current from exceeding 20A with 12V batteries and 12V PV’s. If PV open circuit voltage (V
OC
) ever exceeds
30V which would occur with PV voltage greater than 12V nominal, current limit will become 15A until the 1524 reboots. Note that when the 1524 exits current
limit the charge control system will briefly enter acceptance on it’s way back to MPPT even though battery voltage may be low.
Charge Status Indicator
Shows present charge mode and
approximate battery state of charge.
Auxiliary Output Indicator
Shows when auxiliary output is ON for
load control or auxiliary battery charge.
It is normal for the front panel to be
quite warm to the touch when
operating at high power.
