Installation Instructions for the HCH-1000 Series Capacitive Humidity Sensors GENERAL INFORMATION The HCH-1000 Series is a capacitive polymer sensor designed for relative humidity measurement. The sensor converts humidity value into capacitance, which can be measured electronically. ISSUE 1 50018326 SENSOR OPERATING RANGE Although the HCH-1000 Series may not fail beyond the limits, as shown in Figure 2, the specification only applies to operation within the working range. FIGURE 2: OPERATING RANGE Polyimide is used as a humidity sensing material because of its inherent IC (Integrated Circuit) processing compatibility, reduced temperature dependence and enhanced resistance against contamination. The HCH-1000-Series is manufactured using semiconductor technology. STANDARD CHARACTERISTICS The sensor consists of a grid top electrode, a polyimide layer, and a bottom electrode. The grid top electrode on the bottom electrode provide enhanced sensitivity compared to that of a standard structure. Figure 1 shows the typical response curve in a humidity range of 0% RH to 100% RH. FIGURE 1: TYPICAL HUMIDITY RESPONSE (Sensitivity = 0.6 pF %RH) 390 380 Capacitance (pF) 370 360 350 340 330 320 310 300 290 280 270 0 10 20 30 40 50 60 70 R elative hum idity (%R H ) Sensing and Control 80 90 100 HCH-1000 Series Capacitive Humidity Sensors Issue 1 50018326 SPECIFICATIONS (TA = 25 ºC [77 ºF], Input Voltage = 1 VRMS, Frequency = 20 kHz) Characteristic Normal capacitance Sensitivity Humidity hysteresis Linearity Response time Temperature coefficient Long-term stability (drift) Operating temperature range Operating humidity range Operating frequency range Min. 310 0.55 – – – 0.15 – -40 [-40] 0% 1 Typ. 330 0.6 ±2 ±2 15 0.16 0.2 – – – BASIC CAPACITANCE CHARACTERISTICS Capacitance is measured by applying 1 Vrms at 20 kHz at 25 °C. The sensor characteristic is determined by the following formula: Max. 350 0.65 – – – 0.17 – 120 [248] 100% 100 Unit pF pF/% RH % RH % RH sec pF/°C % RH/year °C [°F] RH kHz Note at 55% RH 10% RH to 95% RH – – 30% RH to 90% RH 5 °C to 70 °C [41 °F to 158 °F] – – – – FIGURE 3: BASIC CAPACITANCE (At 25 °C, 1 VRMS, 20 kHz) CC(%RH) = CS at 55%RH + S x[(%RH(CM) - %RH(CS)]pF Where, S CC(%RH) CS at 55 %RH %RH(CM) %RH(CS) Sensitivity (pF/%RH) Calculated capacitance at the measured relative humidity Standard capacitance value at 55% RH Measured relative humidity value Standard relative humidity value (55% RH) Figure 3 shows the typical characteristic curve. The average increase in capacitance value within the working range of 10% RH to 95% RH is typically 56 pF. HYSTERISIS CHARACTERISTICS Figure 4 shows the hysteresis curve. The hysterisis formula is: Hysteresis Value = C (20% RH ⇒ 95% RH ) − C (95% RH ⇒ 20% RH ) The hysteresis value is measured under 1 pF. The hysteresis of measured samples indicates between ±3% RH at each humidity point. Where, S CM(%RH) CS at 55%RH %RH(CC) %RH(CS) Sensitivity (pF/%RH) Measured capacitance value Standard capacitance value at 55 %RH Calculated relative humidity value at the measured capacitance Standard relative humidity value (55 %RH) 2 Honeywell • Sensing and Control FIGURE 4: HYSTERISIS CHARACTERISTICS HCH-1000 Series Capacitive Humidity Sensors FIGURE 5: TEMPERATURE CHARACTERISTICS (At 1 VRMS, 20 kHz) Issue 1 50018326 FIGURE 7: SHORT-TERM STABILITY FIGURE 6: FREQUENCY CHARACTERISTICS FIGURE 8: MOUNTING DIMENSIONS (For reference only: mm/[in]) HCH-1000-001 HCH-1000-002 Honeywell • Sensing and Control 3 HCH-1000 Series Capacitive Humidity Sensors ENVIRONMENTAL TEST SYSTEM Figure 9 depicts environmental testing. The devices are characterized at 25 °C [77 °F] between 20% RH and 95% RH. The meter is set to measure capacitance at 1 V and 20 kHz. Issue 1 50018326 FIGURE 9: ENVIRONMENTAL TEST SYSTEM DIAGRAM For precise measurement, a hygrometer is compared with the humidity of the temperature-humidity chamber. The data output indicates the effect of sensor characterization before/after the environmental tests. WARNING PERSONAL INJURY DO NOT USE these products as safety or emergency stop devices or in any other application where failure of the product could result in personal injury. Failure to comply with these instructions could result in death or serious injury. WARRANTY/REMEDY Honeywell warrants goods of its manufacture as being free of defective materials and faulty workmanship. Honeywell’s standard product warranty applies unless agreed to otherwise by Honeywell in writing; please refer to your order acknowledgement or consult your local sales office for specific warranty details. If warranted goods are returned to Honeywell during the period of coverage, Honeywell will repair or replace, at its option, without charge those items it finds defective. The foregoing is buyer’s sole remedy and is in lieu of all other warranties, expressed or implied, including those of merchantability and fitness for a particular purpose. In no event shall Honeywell be liable for consequential, special, or indirect damages. SALES AND SERVICE Honeywell serves its customers through a worldwide network of sales offices, representatives and distributors. For application assistance, current specifications, pricing or name of the nearest Authorized Distributor, contact your local sales office or: E-mail: [email protected] Internet: www.honeywell.com/sensing Phone and Fax: Asia Pacific +65 6355-2828 Europe +44 (0) 1698 481481 +65 6445-3033 Fax +44 (0) 1698 481676 Fax Latin America +1-305-883-8257 Fax USA/Canada +1-800-537-6945 While we provide application assistance personally, through our literature and the Honeywell web site, it is up to the customer to determine the suitability of the product in the application. Specifications may change without notice. The information we supply is believed to be accurate and reliable as of this printing. However, we assume no responsibility for its use. Sensing and Control 1985 Douglas Drive North Minneapolis, MN 55422 www.honeywell.com/sensing +1-305-805-8188 50018326-1-EN IL50 GLO Printed in USA July 2007 Copyright © 2007 Honeywell International Inc. 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