High Precision Chilled Mirror Hygrometer

Key features

Accuracy of ±0.1 °C (±0.18 °F)
Precision measurement to -100 °C (-148 °F) frost point (13.8 ppb_V) with no need for additional cooling
Reproducibility of ±0.15 °C (±0.27 °Ffp) at -100 °C (-148 °Ffp) frost point
Simple configuration and operation via touch screen interface
Sensor optimized for fast response to low moisture levels
External 4-wire Pt100 connections
Microscope for visual inspection of condensate on mirror
Compact 19” x 4U package for flexibility of installation
Ethernet or USB connections
SD card data logging

Overview

The S8000 -100 hygrometer directly measures the formation of condensation on a mirrored surface, offering the widest possible measurement range of -100...+20 °C frost/dew point. It uses a unique advanced dual optics system which detects small changes in moisture condensed on the mirror surface. This results in a very high sensitivity and fast response to changes in frost point, even at very low moisture levels where measurements are most challenging. Fully automated control of the system means that no operator intervention is required. The instrument provides a range of Modbus digital communications, and analog outputs allowing it to be monitored remotely or via specific S8000 -100 logging software. 4-wire Pt100 connections are provided on the rear panel for remote mirror temperature monitoring. A high-contrast touch-screen LCD display gives or presents entirely customizable local indication of the measured values, along with a trend graph and fault warnings.

Resources

Dew-Point Sensor
Measurement Range	-100...+20 °C (-148...+68 °F) frost/dew point
Measurement Accuracy*	±0.1 °C (±0.18 °F)
Reproducibility at -100 °Cfp	±0.15 °C (±0.27 °F)
Stability at -100 °Cfp	±0.1 °C (±0.09 °F)
Speed of Response	<2hrs to ±0.25 °C (±0.45 °F) stability @-90 °Cfp (-130 °Ffp) <6hrs to ±0.25 °C (±0.45 °F) stability @-100 °Cfp (-148 °Ffp)
Temperature dependence at -100 °C (-148 °F)	±0.15 °Cfp (±0.27 °Ffp) per 1 °C (1.8 °F) environmental temperature change
Mirror	Gold-plated copper
Temperature Measurement	4-wire Pt100, 1/10 DIN class B
Sample Flow Rate	500...1000 ml/min (recommended 750 ml/min)
Sample Gas Pressure	1.6 bara (23.2 psia) max
Pressure Sensor
Measurement range	0...1.6 bara (23.2 psia)
Measurement Accuracy	Accuracy 0.25% FS Typical Thermal error 1.5% FS Typical Drift 0.2% FS/p.a non-cumulative Temp Comp -20 °C...+80 °C (-4 °F...+176 °F)
Flow Sensor
Measurement Range	0 to 1000ml/min
Measurement Accuracy	±1.5% FS (10...100% of rated flow)
Monitor
Resolution	User selectable to 0.001 °C (0.0018 °F), depending on parameter
Measurement Units	°C dew/frost point, °C temperature, ml/min flow, bara pressure
Calculated units	Relative humidity – %, Absolute humidity – g/m3, ppm_V, Mixing Ratio – g/kg, Wet Bulb Temperature (Twb) – °C, °F, Water Vapor Pressure (wvp) – Pa, Pressure converted DP – °C, °F, Pressure – kPa, Barg, Psia, Psig
Outputs	Analog: 2x active mA outputs, configurable 0...20 mA or 4...20 mA Digital: Modbus RTU over USB Optional: Modbus RTU over RS485/RS232, Modbus TCP over Ethernet Alarm: 1x Process Relay 1x Alarm Relay Both Form C, 1 A, 30 V DC
User Interface	5.7" LCD with touchscreen
Data Logging	SD Card (8GB supplied) and USB interface. Supports SD Card (FAT-32) – 32 GB max. that allows 24 million logs or 560 days, logging at 2-second intervals
Environmental Conditions	+5 °C...+30 °C (+41 °F...+86 °F)
Power Supply	85 to 264 V AC
Power Consumption	185 VA
Mechanical Specification
Dimensions (W x H x D)	440 mm x 185 mm x 515 mm (17.32” x 7.28” x 20.28”)
Weight	22 kg (48.5 lb)
Sample Gas Connections	Inlet: ¼" VCR Outlet: ¼" Swagelok
General
Optional Remote Temperature Probe	4-wire Pt100, 1/10 DIN class B, 2m cable
Calibration	5-point UKAS calibration to -90 °Cfp (-130 °Ffp) + -100 °Cfp (-148 °Ffp)
* Measurement accuracy means maximum deviation between instrument under test and corrected reference. To this must be added the uncertainties associated with the calibration system and the environmental conditions during testing or subsequent use.