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warrenvictron avatar image
warrenvictron asked

Victron MPPT controller Start Voltage.

Victron Mppt controller specifications listed under Nominal Pv power, 12 volts have a condition noted 1a,b which states that the Pv voltage must exceed Vbat + 5 volts.

Is the voltage measured coming from the Pv array measured under Pv open circuit condition or with the controller placing a load on it.

For example the Pv open circuit voltage may currently be 18 volts which would be acceptable under Vbat +5 volts.

If it is measured when the controller is placing a load on it the Pv voltage might be 15 volts which would be unacceptable under vbat +5 volts.

Under what conditions is the voltage measured Pv Open circuit (Voc) or Pv loaded (Vmp)

MPPT Controllers
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Mike Dorsett avatar image
Mike Dorsett answered ·

This will be the "Open Circuit" Voltage, as before the MPPT starts, there is no 'load' on the solar modules. Once the converter starts I've seen the pv voltage drop to within a couple of volts of the battery voltage.

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warrenvictron avatar image warrenvictron commented ·
Thanks Miked thats what I thought as otherwise there would not be many applications where a single 12 volt 150 - 180 watt panel would be viable with their Vmp being between 18.5 to 18.95 volts. Their Voc range is between 22.20 and 22.74 volts .
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