Hi,
Hmm, that picture (in #1) doesn't look much like a "genuine" calibrated Sensiron humidity sensor, but I guess it's a lot cheaper.
The FO anemometer uses only a "mechanical" magnetic reed switch and the vane resistance varies from 660 ohms up to 120 kohms, so a few tens of ohms (of the cable) is unlikely to affect the measurements, provided that a suitable low-pass filter is included (perhaps just a capacitor across the input) to remove any "garbage".
However, issues are more likely to be encountered with the original Fine Offset transmitter, because it uses a rather weak pullup current (~20 uA) for the anemometer. Also, the ADC "ramp" (for the vane) is applied directly to the cable, so radio interference and capacitive cross-coupled "spikes" can cause malfunctions with extended cables.
Cheers, Alan.
Hmm, that picture (in #1) doesn't look much like a "genuine" calibrated Sensiron humidity sensor, but I guess it's a lot cheaper.
(19-04-2015, 02:17)hvalentim Wrote: if you add 15 meters of phone cord extension to the original ~2,5 mt. supplied cable of FineOffset anemometer+wind-vane it works like a charm.
The FO anemometer uses only a "mechanical" magnetic reed switch and the vane resistance varies from 660 ohms up to 120 kohms, so a few tens of ohms (of the cable) is unlikely to affect the measurements, provided that a suitable low-pass filter is included (perhaps just a capacitor across the input) to remove any "garbage".
However, issues are more likely to be encountered with the original Fine Offset transmitter, because it uses a rather weak pullup current (~20 uA) for the anemometer. Also, the ADC "ramp" (for the vane) is applied directly to the cable, so radio interference and capacitive cross-coupled "spikes" can cause malfunctions with extended cables.
Cheers, Alan.