Progress Solar/Wind SLT 700 Series - Page 115

41TriStar MPPT Operator’s Manual
40
Operation
The TriStar MPPT 150V provides seven (7) standard battery charging settings that are selectable with
the settings DIP switches (see Figure 4.1 above). These standard charging settings are suitable for
lead-acid batteries ranging from sealed (gel, AGM, maintenance-free) to Flooded and L-16 cells. In
addition, an 8th charging setting provides for custom set-points using MSView
TM
PC software.
Shared Settings Value Units
Absorption Extension Voltage 12.50 Volts
Absorption Extension Time Absorption Time + 30 minutes
Float Exit Timeout 60 minutes
Float Cancel Voltage 12.30 Volts
Equalize Timeout Equalize Time + 60 minutes
Temperature Compensation Coe󰀩cient
1
- 5
millivolts /
°C / cell
1
25°C reference
Table 4-2. Battery settings that are shared between all battery types
The shared settings in Table 4-2 above are common to all battery types. The following
illustrations graphically explain the shared settings.
Absorption Extension
Figure 4-3. Absorption extension charging prole.
If battery voltage discharges below 12.50 Volts (25.00 Volts @ 24 V, 50 Volts @ 48 V) the pre-
vious night, Absorption charging will be extended on the next charge cycle as shown in gure 4-3
above. 30 minutes will be added to the normal Absorption duration.
1:00 2:00 3:00 4:00 5:00 6:00
12.50 V
Bulk
Extended
Absorption
FloatAbsorption
Absorption Extension Voltage
time (hrs)
Float Time-out
Figure 4-4. Float exit time-out charging prole
After entering Float stage, the controller will only exit Float if the battery voltage remains below
Float voltage for 60 cumulative minutes. In gure 4-4, a system load turns on at 3:30 hrs when the
controller is in Float stage, runs for one hour, and turns o󰀨 at 4:30 hrs. The load current draw is larger
than the charge current, causing battery voltage to drop below Float voltage for 60 minutes. After
the load runs for 60 minutes, the time-out causes the controller to return to Bulk charging, and then
Absorption stage once again. In this example, a load runs continuously for 60 minutes. However,
because the Float exit timer is cumulative, multiple momentary load events that pull the battery
voltage below Float voltage for a combined 60 minutes duration will also force an exit from Float
stage.
Float Cancel Voltage
1:00 2:00 3:00 4:00 5:00 6:00
12.30 V
Bulk
Absorption
Float Cancel Voltage
time (hrs)
Float cancelled this charge cycle
Figure 4-5. Float cancelled charging prole
1:00 2:00 3:00 4:00 5:00 6:00
Float V
Bulk
Float
Absorption
Absorption
60 mins.
below Float
Voltage
time (hrs)
Bulk