10 technical data, 1 specifications, Technical data – ROTRONIC HygroMet MP402H User Manual
Page 17: Specifications, E-m-hm-v1_12

E-M-HM-V1_12
Rotronic AG
Bassersdorf, Switzerland
Document code
Unit
HygroMet MP Humidity Temperature
Meteorological Probe: User Guide
Instruction Manual
Document Type
Page 17 of 20
Document title
© 2009-2011; Rotronic AG E-M-HM-V1_12
10 Technical data
10.1 Specifications
General
HM 2-wire
HM 3-wire
Device type
Humidity temperature probe with
analog output signals
Humidity temperature probe with analog
output signals and RS485 interface
Circuit type
2-wire, loop powered
3-wire
Power supply and connections
HM 2-wire
HM 3-wire
Supply voltage
10…28VDC
V min = 10 V + (0.02 x Load*)
*Load resistance in ohms.
15…24 VDC
0…1 V outputs: 5…24 VDC
0…5 V outputs: 10…24 VDC
Nominal current consumption
2 x 20 mA
< 50 mA
Electrical connections
3 m cable with tinned ends
Polarity protection
Protective diode on V+
Humidity and temperature
measurement
See document E-M-HC2 Probes > Specifications
Calculated parameters
HM 2-wire
HM 3-wire
Psychrometric calculations
Dew point (Dp) above and below freezing
Frost point (Fp) below freezing and dew point above freezing
Wet bulb temperature (Tw)
Enthalpy (H)
Vapor concentration (Dv)
Specific humidity (Q)
Mixing ratio by weight (R)
Vapor concentration at saturation (Dvs)
Vapor partial pressure (E)
Vapor saturation pressure (Ew)
Start-up time and data refresh rate
HM 2-wire
HM 3-wire
Start-up time
14 s (typical)
3 s (typical)
Data refresh rate
5 s (typical)
1 s (typical)