help-common neutral AC power and DC signal noise
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Hi all,
I am trying to read a DC signal from a signal loop that shares the
neutral with an AC power supply.
The AC is 24 VAC and the DC signal is 2-10 VDC.
I plan on using a simple voltage divider to put the signal into an AD
converter. Of my two digital multi meters, one reads pretty stable
the other never settles, so it is seeing some part of the AC in the
signal.
If you have any suggestions or tips on how to eliminate the AC please
let me know.
R-1 D-1 R-2 P-1
Signal ---/\/\---->|----/\/\----[noparse][[/noparse]pot]
gnd
|
= cap
|
to common neutral
Wiper on pot goes to ADC.
I am trying to read a DC signal from a signal loop that shares the
neutral with an AC power supply.
The AC is 24 VAC and the DC signal is 2-10 VDC.
I plan on using a simple voltage divider to put the signal into an AD
converter. Of my two digital multi meters, one reads pretty stable
the other never settles, so it is seeing some part of the AC in the
signal.
If you have any suggestions or tips on how to eliminate the AC please
let me know.
R-1 D-1 R-2 P-1
Signal ---/\/\---->|----/\/\----[noparse][[/noparse]pot]
gnd
|
= cap
|
to common neutral
Wiper on pot goes to ADC.