How to properly measure solenoid coil current. 1

[PowerHydro]

Hi everyone.
Question as in the topic.

For example, I have a hydraulic pump equipped with a proportional solenoid valve that controls pressure.

The solenoid coil is powered by PWM 24 V with a frequency of 200 Hz.
I set PWM to 50% and measure the solenoid coil current.
When I measure with a true RMS multimeter, I have an indication of 0.86 A on the DC range.
When I measure on the AC+DC range, the reading is 1.38 A.

Which measurement is correct?

 

[IRstuff]

Might be neither. PWM @200Hz may not be compatible with your meter's true RMS function

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[PowerHydro]

Many people connect in series and simply measure in the I dc range.
So can you describe how you would measure it?

 

[FacEngrPE]

Sometimes the manual has useful information.

For better accuracy when measuring the dc offset of an ac voltage, measure the ac voltage first. Note the ac voltage range, then manually select a dc voltage range equal to or higher than the ac range. This procedure improves the accuracy of the dc measurement by ensuring that the input protection circuits are not activated.

https://www.fluke-direct.com/pdfs/cache/

http://www.fluke-direct.com/87-5/manual/87-5-manual.pdf

As current measurement is voltage across a resistance, the same stipulation will apply when using a current sensor.

 

[LionelHutz]

AC+DC is more likely to be correct. The AC range is probably blocking the DC offset.

 

[IRstuff]

If you wanted something reasonably accurate, then a SMALL series resistor and an oscilloscope.

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