User manual DELTA-T RHT2NL DATA SHEET

[. . . ] Delta-T Devices Data Sheet Relative Humidity & Air Temperature Sensors Types RHT2nl, RHT2v & AT2 The RHT2 and AT2 sensors are designed for weather station measurements of relative humidity and air temperature. [. . . ] No sensor power requirement. Shielded RH and Temperature Sensors The RHT2 comprises an RH and air temperature transducer housed in the solar radiation shield. The transducer requires power and provides two output signals for the RH and air temperature. RHT2-DS-3a. doc 23/07/03 Plug-in Replacement Modules Routine checking at least once every year is the minimum for RH sensing elements, since the RH element may show some ageing with time. The general recommendation for the replacement interval is every two or three years, in clean atmospheric conditions. If atmospheric pollutants are present, or if the atmosphere is acidic then the replacement must be made every year. Plug-in Replacement Modules minimise the cost and delay of maintenance. They are interchangeable and can be fitted and used without any further calibration. RHT2nl, RHT2v & AT2 Technical Specifications Relative Humidity Sensor [RHT2nl & RHT2v models] RH Output range Sensitivity Ageing characteristic Accuracy at 23°C Humidity linearisation Operating conditions Storage conditions Response time Load impedance Voltage supply Size and Weight Enclosure rating Output range Thermistor resistance Accuracy AT2 probe dimensions Output range Sensitivity Accuracy specifications are subject to change without notice 0 to 100%RH 10 mV per %RH; 0 to 1 V Typical: ~-1. 5 to -2% first year; ~-1% second year; ~-0. 5% third year. ± 2% RH (5 to 95% RH) ± 2. 5% RH (RH<5% and >95%) (hysteresis and non linearity included) 7 points, 6 segments, memorised in the module EEPROM 0 to100% RH, -20 to +80°C -40 to +85°C t <10 s (90% of a step from 11% to 75% RH). > 10 k 5 to 32 VDC, 2 mA RHT2nl, 4 mA RHT2v length 96 mm, 18 mm, 80 g IP65 -50 to +150°C (thermistor only) 2K ohm at 25°C, non-linear ± 0. 1°C over 0 to 70°C 125 mm x 4. 8 mm dia -20 to +80°C 10 mV per °C; 0 to 1 V ± 0. 5% (± 0. 5°C) 22 cm / 12 cm 11 mm UV stabilised thermoplastic 0. 4°C @ 3 m. s-1 0. 65°C @ 2 m. s-1 1. 4°C @ 1 m. s-1 or slower Air Temperature Sensor [ RHT2nl and AT2 models only ] Air Temperature Sensor [ RHT2v model only ] Solar Radiation Shield type SRS2 Overall height / Diameter Plate spacing 3 x Top Plates; 10 x Lower Plates Material Radiation temperature error at 1 kW. m-2 irradiance level: Ordering Information type reference RHT2nl-02 RHT2v-02 RHT2nl-chp RHT2v-chp SRS2 AT2-02 item description RH Sensor and Precision Air Temperature sensor type RHT2nl (2m cable) both mounted in same solar radiation shield. [. . . ] Replacement plug-in RH & Temperature module for RHT2nl sensor Replacement plug-in RH & Temperature module for RHT2v sensor RH/Air Temp Solar radiation shield type SRS2 - suitable for RHT2nl, RHT2v and AT2 units Air Temperature Sensor type AT2 (2m cable) mounted in own solar radiation shield (± 0. 1°C, 0 to 70°C) Delta-T Devices Ltd 128 Low Road, Burwell, Cambridge, CB5 0EJ, UK Tel: +44 1638 742922, Fax: +44 1638 743155, E-mail: sales@delta-t. co. uk, Web: www. delta-t. co. uk RHT2-DS-3a. doc 23/07/03 [. . . ]