Morningstar TRAKSTAR TS-MPPT-60-600V-48, Руководство пользователя

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51 TriStar MPPT 600V Operator’s Manual 50 Operation
Float Cancel Voltage
1:00 2:00 3:00 4:00 5:00 6:00
49.20 V
Bulk Absorption
Float Cancel Voltage
time (hrs)
Float cancelled this charge cycle
Figure 4-4. Float cancelled charging profile
If the battery bank discharges below 49.20 Volts the previous night, Float charging stage will be
cancelled for the next charge cycle. Figure 4-4 above illustrates this concept. At 0:00 hrs (dawn),
battery voltage is below the Float Cancel threshold voltage. The diagram shows where Float
stage would have occurred if Float was not cancelled.
Equalize Time-Out
1:00 2:00 3:00 4:00 5:00 6:00
Absorp. V
Bulk Float Equalize
Equalize timeout
time (hrs)
Equalize V
Figure 4-5. Equalize time-out charging profile
The charging profile in figure 4-5 shows an
Equalize Time-out
event. The time-out timer be-
gins as soon as battery voltage exceeds the Absorption voltage set-point. If there is insufficient
charging current or system loads are too large, the battery voltage may not reach the Equalize
set-point. Equalize Time-out is a safety feature that prevents high battery voltage for extended
periods of time which may damage the battery.
Temperature Compensation
All charging settings are based on 25°C (77°F). If the battery temperature varies by 5°C, the
charging setting will change by 0.60 Volts for a 48 Volt battery. This is a substantial change in
the charging of the battery, and the use of the Remote Temperature Sensor (RTS) is recom-
mended to adjust charging to the actual battery temperature.
The need for temperature compensation depends on the temperature variations, battery type,
how the system is used, and other factors. If the battery appears to be gassing too much or not
charging enough, the RTS can be added at any time after the system has been installed. See
Section 3.4 - Step 7 for installation instructions.
Battery Sense
Voltage drops are unavoidable in power cables that carry current, including the
TriStar MPPT 600V battery cables. If Battery Sense wires are not used, the controller must use
the voltage reading at the battery power terminals for regulation. Due to voltage drops in the
battery cables, the battery power connection voltage will be higher than the actual battery bank
voltage while charging the battery.
Two sense wires, sized from 1.0 to 0.25 mm
2
(16 to 24 AWG), can be used for battery voltage
sense. Because these wires carry no current, the voltage at the TriStar will be identical to the
battery voltage. A 2-position terminal is used for the battery sense connection.
Generally accepted wiring practice is to limit voltage drops between the charger and the battery
to 2%. Even properly sized wiring results in significant voltage drop that can impact charging.
The controller will begin Absorption or limit equalization at a lower battery voltage because the
voltage at the controller’s terminals is higher than the actual battery voltage.
Note that the battery sense wires will not power the controller, and the sense wires will not com-
pensate for losses in the power wires between the controller and the battery. The battery sense
wires are only used to improve the accuracy of the battery charging.
See Section 3.4 - Step 8 for instructions on how to connect the battery sense wires.