Multi-channel current measurement using PaHub and ADC Unit, results are lower than w/o PaHub

[Richelieu]

Hi there,

I am currently using m5stack and ADC Unit to measure target AC cables.
However, when I attempted to use PaHub and 2 ADC Units to create a multi-channel system, the outputs are 20-30% lower than the results of using simply one ADC unit.

Previously, there are a couple of solutions in this forum, like:
https://community.m5stack.com/topic/3040/adc-unit-major-problem?lang=ja
https://community.m5stack.com/topic/1107/solved-fire-pahub-adc-ads1100
I really appreciate it!

However, is there any solution without removing the resistors in ADC unit? Instead, is that possible to remove any resistors in PaHub to correct the outputs?

Any does anyone know the reason/principle of removing resistors?

Thank you very much and I appreciate any reply.

[ajb2k3]

@Richelieu said in Multi-channel current measurement using PaHub and ADC Unit, results are lower than w/o PaHub:

Hi there,

I am currently using m5stack and ADC Unit to measure target AC cables.
However, when I attempted to use PaHub and 2 ADC Units to create a multi-channel system, the outputs are 20-30% lower than the results of using simply one ADC unit.

Previously, there are a couple of solutions in this forum, like:
https://community.m5stack.com/topic/3040/adc-unit-major-problem?lang=ja
https://community.m5stack.com/topic/1107/solved-fire-pahub-adc-ads1100
I really appreciate it!

However, is there any solution without removing the resistors in ADC unit? Instead, is that possible to remove any resistors in PaHub to correct the outputs?

Any does anyone know the reason/principle of removing resistors?

Thank you very much and I appreciate any reply.
Sounds like a power issue, may need to add a power booster

[Richelieu]

@ajb2k3

Thank you very much.
Power booster sounds like a pretty good solution.

I apologize that I am a beginner of this field, if possible, could you please inform me why removing resistors of ADC Unit corrects the current output?

Since I also tried to remove several resistors in PaHub, however, the readings increased only a little bit..