brewdexta
The biggest tool in the box
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I'm using NTC thermistors to measure temperature in the workshop and other barn locations to turn on relays to control valves. The relay unit has digital, analogue and NTC inputs, 8 relays and is controllable via IP.
The sensor needs to be about 10m away from the relay unit so I'm using CAT5E to extend the sensor leads.
The temp wanders all over the place when extended, so much that it's impossible to set reasonabke thresholds, probably about 5c variation.
It's fine when the sensor is connected directly to the unit. So I'm suspecting noise is the issue.
I could try some screened cable, and possibly a low pass filter but thought I would ask if anybody else has experienced this before I sod about. I do have a plan B but would prefer to fix the issue.
Anybody experienced this with NTC sensors and fixed it?
Cheers
Andy
The sensor needs to be about 10m away from the relay unit so I'm using CAT5E to extend the sensor leads.
The temp wanders all over the place when extended, so much that it's impossible to set reasonabke thresholds, probably about 5c variation.
It's fine when the sensor is connected directly to the unit. So I'm suspecting noise is the issue.
I could try some screened cable, and possibly a low pass filter but thought I would ask if anybody else has experienced this before I sod about. I do have a plan B but would prefer to fix the issue.
Anybody experienced this with NTC sensors and fixed it?
Cheers
Andy