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QGC reads incorrect battery voltage

QGC reads 14.1 volts after charging to 15.5 volts. Is this normal?

Can you confirm the battery voltage with a multimeter? What is the difference between voltage displayed in QGC and voltage displayed on the multimeter?

Anyway, you can adjust voltage scaling from the Power tab in the Vehicle Setup page (click the gears icon). Choose ‘other’ for power sensor, then adjust the voltage multiplier until the voltage readout is correct.

Hi Jacob,

Where do I scale the battery voltage in the new QGC?

I am 1.5V out

Cheers,
E.

Hi @etienne,

The proper parameter values for our R2 PSM are listed in the product page here.

-Adam

I have the same thing, but it’s also reading 5.something amps at idle so I just figured this thing pulled a ton of power and brought the voltage down.

I should have been clearer. The voltmultiplier is not listed

not sure what I did but went back to the power tab and found the voltage multiplier there. its all good now:

You can measure the amps with a meter and then go to the power tab and click on calculate and insert your measurement. it should sort that out. it did for me…

Thanks, I’ll give it a try. Think I have an amp clamp around here somewhere…

Hi,

If using our R2 PSM, the correct values are listed in the product page as noted in my post above. These are accurate according to our testing, it should not be necessary to recalculate them.

-Adam

Hi Adam,

Not sure what is going on, I have R2 PSM which I bought a couple weeks ago installed.

QGC is the latest version completely fresh without anything previous.

Companion and ardusub to the latest version as well.

Cheers,
E.

Hi Eienne,

To clarify, have you confirmed the settings I posted above work when input? I’m not sure I understand, are you saying the correct settings I linked were not the default when downloading the new software and reverting to default parameters, or the settings I linked above are not giving accurate readings?

-Adam

Hello Adam,

The voltage multiplier settings from your link do not appear on Parameter - bat, but in Power tab.

The last screenshot I posted is what I have and the voltage multiplier that works for me is 11.311

Cheers,
E.

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Hi Etienne,

Sorry, I’m still not quite sure I understand, might just be the end of the week getting to me. If I understand correctly, the BATT_VOLT_MULT parameter does not come up when you search for it in the parameters tab?

The voltage multiplier of 11.000 should be accurate based on the math in the PSM circuit and was verified by our testing, is there perhaps some voltage drop on the way to the power module that has not been accounted for?

-Adam

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@adam, you need to update QGC.

3.5.0 obscures some parameters under the ‘advanced’ section. I recommend everyone use the search bar in any case, though.

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lol guys

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Yeah, mine doesn’t show BATT_VOLT_MULTI and also looked the same as in post 3 until I went to a different page and returned same as you. The 11.000 multiplier seems to work good for mine.