USER'S GUIDE ® Vaisala HUMICAP Humidity Transmitter Series HMP140A U175EN15
PUBLISHED BY Vaisala Oyj P.O. Box 26 FIN-00421 Helsinki Finland Phone (int.): +358 9 8949 1 Fax: +358 9 8949 2227 Visit our Internet pages at http://www.vaisala.com/ © Vaisala 2006 No part of this manual may be reproduced in any form or by any means, electronic or mechanical (including photocopying), nor may its contents be communicated to a third party without prior written permission of the copyright holder. The contents are subject to change without prior notice.
HMP140A SERIES Operating Manual U175en-1.5 Contents 1. PRODUCT DESCRIPTION ................................................................................................... 1 2. TO BE NOTED WHEN MEASURING HUMIDITY .................................................................. 2 3. INSTALLATION.................................................................................................................... 3 4. 5. 3.1 Selecting the place of installation ....................................
HMP140A SERIES Operating Manual U175en-1.5 This page intentionally left blank.
HMP140A SERIES Operating Manual U175en-1.5 1. PRODUCT DESCRIPTION The HMP140A series transmitters are reliable and easy to use instruments for the measurement of relative humidity and temperature.
HMP140A SERIES Operating Manual 2. U175en-1.5 TO BE NOTED WHEN MEASURING HUMIDITY In the measurement of humidity and especially in calibration, it is essential that the temperature equilibrium is reached. Even a slight difference in the temperature between the measured object and the sensor causes an error. For example, at +20 °C (+ 68 °F) and 50 %RH, a temperature difference of +1 °C between the measured object and the sensor causes an error of +3 %RH.
HMP140A SERIES Operating Manual U175en-1.5 3. INSTALLATION 3.1 Selecting the place of installation Select a place that gives a true picture of the environment or process and is as clean as possible. Air should circulate freely around the sensor. A rapid air flow is recommended as it ensures the same temperature for the ambient air and the sensor head. Install the transmitter in a place where no cold or hot spot can develop.
HMP140A SERIES Operating Manual 3.2.1 U175en-1.5 Mounting the HMP141A The optimal installation of the HMP141A is with the sensor head pointing downwards. Upward mounting should be avoided due to internal heat transfer. 1. Mounting and wiring: cable feedthrough on the surface or in the connection box. 2. Mount the protection lid to the connection box. 3. Push the sensor head through the protection lid as in figure and connect the electronics housing to the connection box.
HMP140A SERIES Operating Manual U175en-1.5 225 Ø 15 Figure 3.2.2 3.2.3 Ø 12 Dimensions of the HMP142A (in mm) Mounting the HMP143A The cable model HMP143A should also be mounted with the sensor head horizontally whenever possible. This model is provided with two plastic nuts and a gasket. Mount the nuts on the sensor head: disconnect the cable from the transmitter, insert the nuts and fasten them on the sensor head. Then reconnect the cable. A mounting flange is also available (see Fig. 3.2.3).
HMP140A SERIES Operating Manual 3.3 U175en-1.5 Electrical connections The wiring can be done in either of the two ways shown in Figure 3.3. mounting on a juction box surface mount GND Tout SHIELD RHout Vs (OHFWULFDO FRQQHFWLRQV 9 RXWSXW (OHFWULFDO FRQQHFWLRQV P$ RXWSXW *1' *1' 7 $ 9V RXW 6+,(/' 7RXW 9 9V 6+,(/' 5+ $ 5+RXW 9 RXW 9V 9V Figure 3.3 Outputs 0...20 mA (4...20 mA) min. 0...1 V 0...5 V 0...10 V 6 Electrical connections 20...35 VDC R (ohm) 12 + L VDC 50 9...
HMP140A SERIES Operating Manual U175en-1.5 3.4 Connectors and potentiometers on the main PCB DISPLAY CONNECTOR Test connector for factory use; leave the jumper as indicated here PROBE CONNECTOR VIO SHIELD GRN YEL BRN Tgain Toffset Test connector for one point calibration Spare jumpers X15 RHoffset Toutput selection Connectors for the current module RHgain X16 Figure 3.4 3.
HMP140A SERIES Operating Manual 3.6 U175en-1.5 Connection to an AC supply The HMP140A transmitters can also be connected to an AC supply without an external rectifier. However, when two or more transmitters are connected to one 24 VAC transformer, a common loop is formed and there is an increased risk of a short-circuit. To avoid this, always use separate floating supply for each transmitter (see Figure 3.6 A).
HMP140A SERIES Operating Manual U175en-1.5 4. CALIBRATION 4.1 One-point humidity calibration The HMP140A series transmitters should be recalibrated approximately once a year. The interval depends on the operating conditions and the required accuracy. One-point calibration can be done with Vaisala’s portable HMI41 indicator equipped with an appropriate probe and optional calibration cable (19116ZZ).
HMP140A SERIES Operating Manual U175en-1.5 • Use the RH offset potentiometer (see Figure 4.2) to adjust the output signal to the value given in the calibration table (Chapter 4.4). • Place the probe into the calibration hole of the NaCl bottle in the calibrator. • Wait for 10 minutes. • Check that the reading corresponds within the desired accuracy to the reading given in the calibration table. If not, adjust the reading with the RH gain potentiometer (see Figure 4.2).
HMP140A SERIES Operating Manual U175en-1.5 4.4 Calibration table Temperature *) LiCl 4...20 mA 0...20 mA 0...1 V 0...5 V 0...10 V °C °F %RH mA mA V V V 15 59 *) 20 68 11.3 5.81 2.26 0.113 0.565 1.13 25 77 11.3 5.81 2.26 0.113 0.565 1.13 30 86 11.3 5.81 2.26 0.113 0.565 1.13 35 95 11.3 5.81 2.26 0.113 0.565 1.13 NaCl 4...20 mA 0...20 mA 0...1 V 0...5 V 0...10 V %RH mA mA V V V 75.6 16.10 15.12 0.756 3.780 7.56 75.5 16.08 15.10 0.755 3.775 7.55 75.3 16.05 15.06 0.753 3.765 7.53 75.1 16.
HMP140A SERIES Operating Manual U175en-1.5 6. TECHNICAL DATA 6.1 Relative humidity Measurement range 0...100 %RH Accuracy (including non-linearity and repeatibility) when calibrated against salt solutions (ASTM E104-85): 0...90 %RH +2 %RH 90...100 %RH +3 %RH Temperature dependence: dRH (%RH) 2 1.5 1 0.5 0 -0.5 -1 -1.5 -2 -20 -10 0 10 Response time (90%) 20 30 40 50 60 T (°C) 15 s at +20 °C in still air (with sintered filter) Maximum error between the display and the outputs 0.
HMP140A SERIES Operating Manual U175en-1.5 6.3 General Power supply current outputs: min. 20...35 VDC 12 + RL(ohm) 17...24 VAC 50 0...1 V 0...5 V 0...10 V 9...35 VDC 15...35 VDC 20...35 VDC 9...24 VAC 12...24 VAC 16...24 VAC Current consumption 6...10 mA + output currents Electrical connections screw terminals for 0.5 - 1.5 mm2 wires (AWG 15...20), stranded wires recommended Alternative analogue output signals (scalable) 0...20 mA (4...20 mA) 0...1 V, 0...5 V, 0...
HMP140A SERIES Operating Manual 6.4 Electromagnetic compatibility 6.4.1 Emissions Test: Setup according to: Radiated interference EN55022 6.4.2 7. U175en-1.
U175en-1.5 HMP140A SERIES Operating Manual Exceptional operating conditions, damage due to careless handling and misapplication will void the guarantee.
HMP140A SERIES Appendix 1 U175en-1.5 APPENDIX 1: CURRENT OUTPUT MODULE Current module X15 Spare jumpers T output selection X16 RH output selection Figure 1 The current module is available only for HMP142A and HMP143A transmitters. To install the current module to connectors X15 and X16, first disconnect the jumpers (4 pcs). Insert them to the connector for spare jumpers (see Figure 1) and install the current module. Note that the module must be installed exactly as indicated in Figure 1.
HMP140A SERIES Appendix 2 U175en-1.5 APPENDIX 2: SETTINGS OF THE LOCAL DISPLAY °F RH/T °C Figure 1 Location of the RH/T button and the °C/°F jumpers The reading on the local display (relative humidity or temperature) can be chosen by pressing the RH/T button beside the display. At power-up, the display always shows the relative humidity reading. This can be changed to temperature reading by pressing the RH/T button once. Further pressings will change the reading between RH and T.
HMI41 Appendix 2 2 HMI41-Uxxxen-1.
HMP140A SERIES Appendix 3 U175en-1.5 APPENDIX 3: HMP143A PROBE CABLE EXTENSION The cable of the HMP143A probe can be extended up to 100 metres with the help of the extension set including a junction box (part no. 19326) and a shielded six wire extension cable (part no. 1535). The junction box has a 5-pole terminal block and two PG9 lead-throughs. The extension cable is a shielded 6 x 0.22 mm 2 copper wire cable. This cable enables the extension without the need for transmitter adjustments.
HMP140A Appendix 3 U175en-1.5 TECHNICAL DATA Junction box (part no. 19326) Housing: material dimensions classification temperature range ABS plastic 65 x 50 x 35 mm (l x w x h) IP 65 -40...+80 °C Lead-throughs: size cable diameter housing classification PG 9 4...7 mm IP 68 Terminal block: max. wire area 1.5 mm2 Extension cable (part no. 1535) Type Wire resistance Covering Cross-sectional area of the wires Cover Temperature range Wire colours 2 PFSK 6 x 0.
www.vaisala.
