MS - TH Temperature and humidity sensor

Description

In addition to temperature measurement, the MS-TH measures relative humidity. The device used for humidity sensing is a Honeywell part, number HIH-4000. The linearity from 0% to 100% humidity is +/- 0.5%. Accuracy with +5 Vcc is 2% over the full range at 25°C. Response time in slow moving air is typically 30 seconds. The Vcc supply must be sustained above 4 VDC, with 5 VDC being optimal. When using a Link45 or Link12, humidity will be reported in the range of 0.8 VDC (zero percent humidity) to 4.07 VDC (100% humidity). When using a LinkTH, the readings will be converted to % humidity.

Temperature measurement method, and specifications are identical to the MS-T.

MultiSensors, like all 1-Wire slaves, can operate on "parasitic" power. That is, they use the power contained in data signal of the 1-Wire bus, with a capacitor to sustain them during the zeros. Unlike most other 1-Wire devices, MultiSensors have an AUX jumper. This jumper connects the Vcc line on the sensor directly to the power source of the serial port (via the master Link), thus providing a constant Vcc to the sensor independent of what the line signal doing. The AUX jumper is set to provide Vcc when shipped from the factory.