Mastervolt MPPT Solar ChargeMaster 25

6
MPPT Solar ChargeMaster 25 – User and Installation Manual
3 OPERATION
3.1 GENERAL
The Mastervolt Solar ChargeMaster is a fully automatic
battery charger which converts power from photovoltaic
(PV) array to a regulated battery voltage. The PV array
connected to the Solar ChargeMaster is operated at its
optimum voltage to obtain an optimal yield (Maximum
Power Point tracking). The Solar ChargeMaster will
automatically adjust itself to a 12V or a 24V system. Under
normal circumstances the Solar ChargeMaster remains
switched on with the PV-array and batteries connected.
When power from the PV array is enough, the Solar
ChargeMaster will initiate the charging process.
WARNING
The Solar ChargeMaster has no on/off switch.
Charging will be initiated as soon as power
from the PV-array becomes available.
The Solar ChargeMaster is protected against overload,
short circuit, overheating and under and over voltage.
CAUTION!
The Solar ChargeMaster is not protected
against:
• Excessive overvoltage on the Solar input;
• Surges inducted by lightning.
3.2 MAINTENANCE
No specific maintenance to the Solar ChargeMaster is
required. Examine your electrical installation on a regular
base, at least once a year. Defects such as loose
connections, damaged wiring etc. must be corrected
immediately.
If necessary, use a soft clean cloth to clean the casing of
the Solar ChargeMaster. Do not use any liquids or corrosive
substances, such as solvents, alcohol, petrol or abrasive
components.
In the event of decommissioning, refer to section 4.11
3.3 THREE STEP CHARGE ALGORITHM
See Figure 3. Battery charging is accomplished in three
automatic stages: BULK, ABSORPTION and FLOAT.
Figure 3: Three step charge system
• BULK: At this stage the charger delivers its maximum
current for quick charging from 0 to 80%.
• ABSORPTION: The charger has reached its maximum
charge voltage and the charge current will slowly
decrease until the battery is charged up to 100%.
• FLOAT: This stage begins once the battery is fully
charged. The battery remains in fully charged state.
By installing the battery temperature sensor, the charge
voltages are automatically adapted for deviating
temperatures.
Figure 4: Temperature compensated charging
See Figure 4. When the battery temperature is low, the
charge voltage increases. On the other hand, when the
battery temperature is high, the charge voltage is
decreased. Overcharge and gassing are prevented this
way. This will extend the life of your batteries.