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How to verify MPPT is outputting selected charge volts?

May be a silly question. 4892aba9-47ee-4556-b619-f0d9538efca3.pngI know that battery voltage is not indicator of actual output voltage from the charger. How do I measure or see the actual voltage outputting from charger

MPPT SmartSolar
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wkirby answered ·

The Voltage shown as "Battery Voltage" is the actual Voltage present on the battery terminals of the MPPT at that specific time.
When the MPPT is charging, the Voltage at the battery terminals themselves would be a little bit lower due to slight Voltage drop over the cables between the MPPT terminals and the battery terminals.
When the MPPT is not charging, at night for example, then the Voltage shown as "Battery Voltage" will be pretty much spot on due to almost no current in the cables.

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Thanks, think I understand that. Cables to the battery are 4 feet so not sure I can measure the drop with my meters. Will give it a go. Anyway to see or measure the actual output of the controller?

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wkirby avatar image wkirby ♦♦ done commented ·

According to your screenshot, the actual output of the controller is 12.27V. You could also verify this with a meter on the battery terminals of the MPPT.

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done avatar image done wkirby ♦♦ commented ·

If that is the controller output, it leads to the question why so low when bulk is set more like 14.4v. Battery bank is needing charged at about 80%

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wkirby avatar image wkirby ♦♦ done commented ·

The bulk setting is a target Voltage. This is the Voltage that the charge controller is going to try to push the battery Voltage up to as it charges. You have to allow time for the battery to charge.
The battery is at a low Voltage because it is discharged. You can see 29A of current going into the battery. This current will cause the battery to charge and as it charges the battery Voltage will increase.
When the battery Voltage reaches 14.4V, then the charge current will start to gradually decrease as the MPPT holds the battery Voltage at 14.4V during the Absorb phase.
When the Absorb phase is over then the MPPT will stop or slow down charging to allow the battery Voltage to decrease to the Float Voltage setting. The MPPT will again, try to maintain this Float Voltage until there is not enough PV power anymore.

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