For the MicroNet sensors MN-Sx and MN-SxHT, what is the drift factor per year?

Issue

For the MicroNet sensors MN-Sx and MN-SxHT, what is the drift factor per year?

Product Line

TAC I/A Series

Environment

  • MN-Sx
  • MN-SxHT
  • MicroNet Controllers

Cause

There is slight temperature drift with MicroNet Sensors.

Resolution

The non-humidity units (MN-Sx) use a glass encapsulated thermistor sensor that has a maximum drift of .022ºC in the first 30,000 hours (about 3.5 years) and is basically stable after that. The electronics uses precision resistors as references that are powered at less than 1/100 rated power. Using the shelf life specification for drift of 100PPM / year for the reference resistors would add another .022ºC / year. A conservative number of 0.03ºC / year would cover it.

The humidity units (MN-SxHT) have a solid-state sensor with a humidity drift of 0.5%RH / year and a temperature drift of 0.04ºC / year maximum. The sensing chip communicates digitally with a microcontroller so there is no electronics related error.