Analog voltage divider (SKU:DFR0051) for PV voltage measurement

Hi!
Any view on if it is suitable to connect the Voltage Divider (SKU:DFR0051) sold by Core Electronics to measure the voltage of a PV panel (max. goes to around 17V). The voltage divider is then connected to a National Instruments data Acquistion device which accepts voltages upto 10V .

The (SKU:DFR0051) is stated to reduce its input voltage by four times. Thus I feel the divider can do the work to reduce the volatge up to the input voltage suitable for our data acquisition device.

Thanks !

Hi Nuz,

Thanks for your message. Am I overlooking something here - why not use two resistors in a voltage divider configuration? If you used something easy such as a 1:10 ratio then every 1V = 10V. This means the max measurable voltage would be 1.7V.

You could get the full window of operation by using 10:17 ratio; which means for every 10V you are measuring 17V. That, or change the Vref of the test equipment to 1.7V and use the 1:10 ratio. Lotâ€™s of options, all up to you. Whichever configuration you use, the actual voltage can be calculated with the divider ratio in mind.

If the voltage divider is an option then here is a voltage divider calculator. Perhaps the key issue you will run into either way is the input impedance of whatever the device you are measuring with - you want it to be as high as possible as to not draw excessive current from the panels but allow accurate readings to be taken.

Regarding the DFR0051 - it will step down the voltage 5x, which doesnâ€™t seem necessary if you have a couple of resistors around.

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Yes thatâ€™s a simple and excellent way of doing it . Thanks

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Yes, I often have a set-up like this on my Arduino based PCB, so that I can measure the voltage of the battery supplying the Arduino. Easy to program in some check and blink a led (crazily) if the voltage goes below a certain level.

Saves having to measure voltage with a voltmeterâ€¦to find out if it needs charging.

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