USER'S GUIDE ® Vaisala DEWCAP Precision SAW Hygrometer DM500 M210205EN-D
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.
________________________________________________________________________________ Table of Contents CHAPTER 1 GENERAL INFORMATION............................................................................ 7 About This Manual ................................................................... 7 Version Information ............................................................... 7 Feedback............................................................................... 7 Safety.................................
User's Guide ______________________________________________________________________ CHAPTER 5 INFORMATION ON OPTIONAL PARTS .....................................................31 Optional Heated Gas Tubes...................................................31 Optional External Temperature Sensor................................32 Wetted Materials of the Optional Parts ................................33 CHAPTER 6 SETTING UP FOR OPERATION .................................................................
________________________________________________________________________________ CHAPTER 11 MEASUREMENT SETTINGS....................................................................... 59 Automatic Frost Detection .................................................... 59 Forced Freezing...................................................................... 60 Cooling Method Air/Water ..................................................... 60 Statistical Filtering ................................................
User's Guide ______________________________________________________________________ S Stopping the Continuous Output.................................87 ADDR Setting the Device Address.................................87 SEND Outputting One Single Reading ..........................87 INTV Setting the Output Interval ....................................87 FORM Defining the Output Format ................................88 Operational Commands .........................................................
________________________________________________________________________________ MI70 LINK PROGRAM............................................................................... 111 Installation ............................................................................ 111 Device Name MI70ÙDM500 ................................................ 111 Displayed Quantities............................................................ 112 Sensing Unit Status ......................................................
User's Guide ______________________________________________________________________ Humid Air Volume/Dry Air Volume PPMv ...........................132 Effect of Pressure on Dewpoint ..........................................132 Using a Condensation Hygrometer ....................................
Chapter 1 ________________________________________________________ General Information CHAPTER 1 GENERAL INFORMATION This chapter provides general notes for the product. About This Manual This manual contains instructions for performing accurate dewpoint measurements with Precision SAW Hygrometer DM500.
User's Guide ______________________________________________________________________ Safety General Safety Considerations Throughout the manual, important safety considerations are highlighted as follows: WARNING Warning alerts you to a serious hazard. If you do not read and follow instructions very carefully at this point, there is a risk of injury or even death. CAUTION Caution warns you of a potential hazard.
Chapter 1 ________________________________________________________ General Information ESD Protection Electrostatic Discharge (ESD) can cause immediate or latent damage to electronic circuits. Vaisala products are adequately protected against ESD for their intended use. However, it is possible to damage the product by delivering electrostatic discharges when touching, removing, or inserting any objects inside the equipment housing.
User's Guide ______________________________________________________________________ - Anslut inte brandfarliga, mycket reaktiva eller giftiga gaser till instrumentet. Se till att ventilationen är tillräcklig vid användning av andra gaser än luft. - Sätt inte samman instrumentet i en lokal där kondensvatten som droppar ut ur systemet kan orsaka en farlig situation, till exempel ovanpå högspänningsutrustning.
Chapter 1 ________________________________________________________ General Information - Non posizionate lo strumento in un luogo dove l'acqua condensata che fuoriesce dal sistema potrebbe causare un pericolo, come su alimentatori elettrici ad alto voltaggio. - Quando la funzione di riscaldamento è attiva, non toccate a mani nude il tappo caldo della camera di misurazione. Si prega di usare dei guanti per togliere il tappo.
User's Guide ______________________________________________________________________ - Raak het hete kapje van de sensorbehuizing niet met blote handen aan als de verwarmingsfunctie is geactiveerd. Maak het kapje alleen los met handschoenen aan. Trademarks Microsoft®, Windows®, and Windows NT® are registered trademarks of Microsoft Corporation in the United States and/or other countries. License Agreement All rights to any software are held by Vaisala or third parties.
Chapter 2 __________________________________________________________ Product Overview CHAPTER 2 PRODUCT OVERVIEW This chapter introduces the features and advantages of Precision SAW Hygrometer DM500. Product Description DM500 is a high accuracy dewpoint temperature measuring instrument capable of measuring dewpoints down to -75 ºC with an accuracy of ± 0.2 ºC. The DM500 system consists of the user interface unit DMI500 and the dewpoint sensing unit DMP501.
User's Guide ______________________________________________________________________ - Air flow rate flow (slpm, scfh) The DM500 system includes two packages including the following parts: DMI500 - DMI500 user interface unit - Serial cable for EIA-232 (RS232) - CD-Rom including MI70 Link software; to transfer logged data to your PC - Power cable (according to the customer's requirement) DMP501 - DMP501 dewpoint sensing unit - Swagelok spare tube fittings for 1/4" tubes for the sample gas line (to replace de
Chapter 2 __________________________________________________________ Product Overview Front Panels Figure 1 DMI500 User Interface Unit Front Panel The following numbers refer to Figure 1 above: 1 2 = = 3 = 4 = Mains switch . Press to turn the device on/off. Configurable softkeys . Press down to activate the menu function shown beside the button. Arrow keypad ►. Press any of the arrow buttons to open path for the menus. In the menus, you can navigate with arrow buttons.
User's Guide ______________________________________________________________________ Figure 2 DMP501 Dewpoint Sensing Unit Front Panel The following numbers refer to Figure 2 above: 1 2 3 NOTE = = = Power/data cable; connect to the back panel of the DMI500. Allen screw for adjusting the sample flow. Sensor cup; three Allen screws to open the cup for sensor cleaning.
Chapter 2 __________________________________________________________ Product Overview Back Panels 1 C NO NC REL 1 C NO NC REL 2 5 6 Figure 3 3 2 4 DMI500 User Interface Unit Back Panel The following numbers refer to Figure 3 above: 1 2 3 4 5 6 = = = = = = Relay outputs (optional) Serial port (EIA-232, RS232 for Terminal/MI70-link Connection to DMP501 Mains cable RS485 and LonWorks-port (optional) Analog outputs (optional) VAISALA _________________________________________________________________
User's Guide ______________________________________________________________________ 3 4 5 2 6 7 8 1 9 Figure 4 DMP501 Dewpoint Sensing Unit Back Panel The following numbers refer to Figure 4 above: 1 2 3 4 5 6 7 8 9 NOTE = = = = = = = = = Water In (WI) Gas In (GI) Connection to DMI500 Relay for heated sample lines Water Out (WO) Temperature sensor connection (optional) Service switch 4: Adjustment enable switch Gas Out (GO) Serial port EIA-232, RS232 The DM500 shall always be operated in horiz
Chapter 2 __________________________________________________________ Product Overview Optional Accessories and Spare Parts Description Accessories Rack mounting kit Portability kit Extension cable 2.
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Chapter 3 ______________________________________________________ Functional Description CHAPTER 3 FUNCTIONAL DESCRIPTION This chapter describes the functionality of the product. DM500 Principle of Operation DM500 is an automatic, continuously controlling condensation hygrometer designed to measure dewpoint temperatures from -75 ºC to +60 ºC, depending on the model. The system consists of the DMP501 dewpoint sensing unit and the DMI500 user interface unit.
User's Guide ______________________________________________________________________ Sensing Element The DEWCAP® SAW sensor, as used in the condensation hygrometer, integrates the cooled surface (where condensation forms) with the detection mechanism in one element. The element consists of a transmitting and a receiving antenna photolithographically patterned on a single mechanically very durable crystal quartz chip.
Chapter 3 ______________________________________________________ Functional Description Contamination and Chemical Resistance The DM500 operates reliably even with substantial particulate contamination on the sensing element. Analysis of frequency and impedance makes it possible to distinguish between frost and dew and to give warning of hygroscopic contaminants on the detector. Use of a quartz wafer as a sensor substrate results in excellent resistance to aggressive chemicals.
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Chapter 4 _________________________________ General Information About Sampling and Results CHAPTER 4 GENERAL INFORMATION ABOUT SAMPLING AND RESULTS This chapter provides you with useful information concerning gas sampling and the effects that different parameters have on the measurement results. Gas Sampling When measuring low dewpoints, all installations must comply with the strict requirements.
User's Guide ______________________________________________________________________ - Sample tubing shall be as short as possible, the surface area should be minimized by using the tubing with the smallest diameter that the flow conditions shall permit - Surface finishing of wetted surfaces is important, polished or electropolished steel is recommended for best results - Avoid hygroscopic materials in the sampling lines, use stainless steel membranes instead of rubber membranes - Choose impermeable materia
Chapter 4 _________________________________ General Information About Sampling and Results The Effect of the Ambient Temperature on Cooling Capacity The cooling capacity of the sensor is dependent on the cooling air temperature, as shown in Figure 7. In general, the cooler the ambient air is, the lower dewpoint can be reached. By using air as a cooling medium, the lowest normally achievable dewpoint is about -50 ºC. When measuring lower dewpoint, water cooling must be used. Recommended air temperature: 10.
User's Guide ______________________________________________________________________ The Effect of the Liquid Coolant Temperature on Cooling Capacity The cooling capacity of the sensor is dependent on the cooling water temperature, as shown in Figure 8. Recommended water temperature: < 15 ºC (50 ºF). Figure 8 Effect of Water Temperature on Lowest Achievable Stable Sensor Temperature Sample gas flow in the above Figure 8 1.0 slpm; Tamb 23 ºC; water flow 5 l/min.
Chapter 4 _________________________________ General Information About Sampling and Results The Effect of the Sample Gas Flow Rate on Cooling Capacity and Result Deviation The cooling effect of the gas flow rate is shown in Figure 9 (on the right). Low flow rate increases cooling capacity but also increases response time. -72 -73 Tsensor /C -74 -75 -76 -77 -78 -79 0 0.5 1 1.5 2 2.
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Chapter 5 ________________________________________________ Information On Optional Parts CHAPTER 5 INFORMATION ON OPTIONAL PARTS This chapter provides you with information on the optional parts of the DM500.
User's Guide ______________________________________________________________________ External gas tubes The heating of the external gas tubes shall be taken care by the user. The external lines shall be heated before letting the sample gas flow in the lines. This is to avoid condensation problems. To facilitate external gas line heating control, the relay output on the back plate of the DMP501 activates when heating is ON.
Chapter 5 ________________________________________________ Information On Optional Parts Wetted Materials of the Optional Parts Pump Polyarylamide, NBR (nitril butyl rubber), galvanized steel.
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Chapter 6 _____________________________________________________ Setting up for Operation CHAPTER 6 SETTING UP FOR OPERATION This chapter provides you with information that is intended to help you set up the product for operation. Connection of the DMI500 and DMP501 Units Unpack the instrument carefully and check that all parts are visually undamaged.
User's Guide ______________________________________________________________________ Swagelok tube fittings' installation instructions CAUTION 1. Insert the tubing into the Swagelok tube fitting. Tubing should rest firmly on the shoulder of the fitting. The nut should be finger tight. 2. Mark the nut at the 6 o'clock position. 3. Hold the fitting body with a backup wrench and tighten the nut 1¼ turns. Watch the marking and make one complete turn and continue to 9 o'clock position.
Chapter 6 _____________________________________________________ Setting up for Operation Figure 13 ¼" Swagelok Adapter Fitting Connected to the Standard Swagelok 6 mm Connector The following numbers refer to the enlarged area of Figure 13 above: 1 2 = = Grooves No groove To connect the ¼" adapter fitting, first disconnect the standard elbow fitting. Notice how the millimeter-fittings have small grooves on them. When the grooves face, the adapter fitting is connected the right way.
User's Guide ______________________________________________________________________ 6 mm fitting with the ¼" adapter fitting (provided), if needed. If you use the adapter fitting, see that the 6 mm side is connected to the Gas In -connection. NOTE WARNING 2. Attach the gas tubes (diameter of 6 mm or ¼") to the Swagelok fittings. 3. Replace the Swagelok fitting (with the tubing) into the GI connector (connect the Gas Out tubing similarly, if necessary).
Chapter 6 _____________________________________________________ Setting up for Operation NOTE To avoid condensation into the internal gas tubes and sensor, stop cooling water flow if measurement is stopped and Td of sample gas may be higher than the cooling water temperature. Connecting the Cooling Liquid 2 1 Figure 15 DMP501 Back Panel, Connectors for Cooling Liquid The following numbers refer to Figure 15 above: 1 2 = = Water In (WI) Water Out (WO) 1.
User's Guide ______________________________________________________________________ Connecting the Condensation Water Drain Tube Significant moisture condensation occurs only if the system is watercooled. Connect the condensation water drain tube to the outlet situated on the right-side panel of the DMP501. WARNING 1. Connect the silicone tube to the metal tube protruding from the right side of the DMP501 Dewpoint Sensing Unit. 2.
Chapter 7 _____________________________________________________ Measuring the Dewpoint CHAPTER 7 MEASURING THE DEWPOINT This chapter provides instructions on how to conduct dewpoint measurements with the DM500, and contains additional information about the moisture phases. Dewpoint Measurement with DM500 Do not assemble the instrument in a location where condensed water dripping out of the system could cause a hazard, like above highvoltage power supplies. 1.
User's Guide ______________________________________________________________________ 5. To achieve the optimum measuring results, clean the sensor and determine the clean sensor value before the first measurements, see page 65. 6. Start measurement by pressing 7. Wait until yellow led turns to green in the DMP501 dewpoint sensing unit front panel. The symbol disappears from the display and the error limit value appears on the upper right corner of the display. The measuring cycle is now balanced.
Chapter 7 _____________________________________________________ Measuring the Dewpoint automatically converted to a corresponding dewpoint temperature, which is then displayed to the user. The symbol on the display changes to 7 after the freezing is complete.
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Chapter 8 ________________________________________________________ Displays and Menus CHAPTER 8 DISPLAYS AND MENUS This chapter describes the user interface.
User's Guide ______________________________________________________________________ Error limit: The 2σ deviation of the measured sensor temperatures. Appears when the system is balanced and statistical filtering activated. During an unstable intermediate moisture phase indicated by blinking 6 and 7 symbols, error limit value is higher than in stabilized state. Preset value(s): All the preset values are shown in the header if they are not selected for the display.
Chapter 8 ________________________________________________________ Displays and Menus Menus and Navigation In the menus you can change settings and select the functions. 1. Open the main menu by pressing any of the 2. Move in the menus by using 3. Select the item with 4. Press 5. Press EXIT to return you back to the main view. Figure 18 buttons. buttons. button. to return to the earlier level.
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Chapter 9 _____________________________________________________________Basic Settings CHAPTER 9 BASIC SETTINGS This chapter provides instructions on how to make the basic settings. User Interface Setting the Language 1. Open the MENU: press . 2. Select ►Settings, press 3. Select ►User Interface, press 4. Select Language, press 5. Select the language (English/ German/ French/ Finnish/ Spanish) and press SELECT. 6. Press . . SET. EXIT to return to the main view.
User's Guide ______________________________________________________________________ 5. Press the shortcut key you want to change, for example ►Measurement settings. 6. Select the new shortcut function by using arrow buttons, press SELECT. Answer YES to confirm your selection, otherwise answer NO and continue from item 4. 7. Press EXIT to return to the main view. Key Click ON/OFF You can turn the button pressing sound effect on or off. 1. Open the MENU: press . 2. Select ►Settings, press 3.
Chapter 9 _____________________________________________________________Basic Settings Device Information The basic information about the DM500 is found as follows: 1. Open the MENU: press 2. Select ►Settings, press 3. Select Device information, press 4. The display gives the basic information on the device. Press MORE to get more information and EXIT to return to the main view. . . SHOW.
User's Guide ______________________________________________________________________ Reverting Factory Settings Factory settings can be reverted to clear all changed settings and data memory. Reverting factory settings does not affect sensing unit calibration. 1. Open the MENU: press . 2. Select ►Settings, press 3. Select Factory settings, press the reverting. 4. The device resets automatically. . REVERT.
Chapter 10 __________________________________________________________ Display Settings CHAPTER 10 DISPLAY SETTINGS This chapter describes the display settings. Display Backlight The display backlight is automatically on when the device is turned on. After 10 hours use, the backlight turns off. When pressing any button, the light turns on again.
User's Guide ______________________________________________________________________ 2 If sampling from process, parameter is relevant only if the optional pressure sensor is used.(or if the actual P value is set manually) 3 If sampling from process, parameter is relevant only if the optional flow sensor is used (or if the actual Flow value is set manually). More about the difference between Td/f and Td on page 128. To select the displayed quantities: 1. Open the MENU; press . 2.
Chapter 10 __________________________________________________________ Display Settings 6. To view the saved readings, open the menu, select Recording/Viewing, press , select View recorded data, press . 7. Select the file marked with , press SHOW. Now you can see the firstly saved data reading on the display numerically and pointed out in graphics with a vertical line (the curve shows all the individual data points). Press to see the next data point numerically etc.
User's Guide ______________________________________________________________________ 4. Press NEXT to see the graphic trend of the other parameters. 5. Press INFO to see the statistics of the saved data. 6. Press OPTIONS to set the following graph options Show value: Select YES to have the data shown numerically. Select NO to hide the numerical value. Hide function keys: Select YES to hide the function keys shown in the right side of the display. Select NO to have the function keys shown.
Chapter 10 __________________________________________________________ Display Settings 1. Open MENU: press . 2. Select ►Display, press 3. Select Quantity, press press SELECT. 4. Select Alert above, press SET. (In case you want to delete the setpoint, press DELETE and go to item 6). 5. Press Press 6. Select Alert below, press SET. (In case you want to delete the setpoint, press DELETE and go to item 8). 7. Press Press 8. Select ENABLED WHEN, press SELECT.
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Chapter 11 _____________________________________________________ Measurement Settings CHAPTER 11 MEASUREMENT SETTINGS This chapter provides you with information about the measurement settings. Automatic Frost Detection The automatic dew/frost sensing procedure senses if the condensation on the sensor is water (dew) or ice (frost). If the sensing is turned off, the Td/f value can be either dewpoint or frostpoint, depending on the sensor state. Then the other water content quantities are disabled.
User's Guide ______________________________________________________________________ Forced Freezing In some measurement conditions there may be formation of a two phase system, ice-dew, on the sensor. This situation is dynamic and the time needed to reach an equilibrium may be rather long. To avoid an unstable phase transition, the DM500 has a function for generating a stable layer of frost on the sensor right from the beginning of the measurement.
Chapter 11 _____________________________________________________ Measurement Settings NOTE Select the water cooling only if the water is actually supplied to the sensing unit. Otherwise the sensing unit can be overheated To select the cooling method: 1. Open MENU: press . 2. Select ►Measuring, press 3. Select ►Measurement settings, press 4. Select Cooling method. 5. To select air cooling, press 6. To select water cooling, press 7. Press . . AIR. WATER. EXIT to return to the main view.
User's Guide ______________________________________________________________________ Response Speed You can set the response speed to stable, normal (default) or fast. If fast transients in the dewpoint prevent the system from reaching balance, the signal can be stabilized by selecting the Stable response speed. Fastest response time is achieved by setting the speed to Fast but this may increase the noise in the dewpoint measurement.
Chapter 11 _____________________________________________________ Measurement Settings Transient Recovery Time The transient recovery time is the time the sensor waits before starting the fast recovery cycle after rapid dewpoint change. If there are large, rapid step changes in humidity level the shorter transient recovery times are recommended. If the changes are slow (like typically at low dewpoints), the longer transient recovery times are recommended.
User's Guide ______________________________________________________________________ 6. Set the new value by using numerical buttons. 7. Press OK to confirm the settings. 8. Press EXIT to return to the main view. The Process variables selection menu is only available for those parameters that are set, not measured.
Chapter 12 ___________________________________________________ Self Diagnostics Settings CHAPTER 12 SELF DIAGNOSTICS SETTINGS This chapter describes the self diagnostic functions settings. The DM500 goes through a self diagnostics procedure when the power is switched on. If an error is found, the error display tells about it. However, there are some self diagnostics operations that the user can set, such as Salt detection, Sensor circuit check and Cooling capacity test.
User's Guide ______________________________________________________________________ If the salt detection sees salt on the sensor (message on the display), please clean the sensor carefully, see page 113. The salt warning message is shown when the measured value decreases below 80 % of the salt detection limit. It is not recommended to use serial commands during the salt detection. Salt detection interrupts the dewpoint measurement for approximately one minute.
Chapter 12 ___________________________________________________ Self Diagnostics Settings the sensor is desired, you can set the automatic checking interval (1...99 h) as follows: 1. Open MENU: press 2. Select ►Measuring, press 3. Select ►Self diagnostics, press 4. Select Sensor circuit chk. 5. To turn on the sensor checking circuit and set the checking interval, press SET. 6. Set the interval (1...99 h) by using the numerical buttons. 7. Press OK to confirm the setting.
User's Guide ______________________________________________________________________ The serial output command R shows frozen values. You can cancel the testing sequence by pressing the CANCEL. 6. When the test is completed, you see the following display: 7. Press EXIT to return to the main view. The following factors affect the cooling capacity: - Temperature of the environment - Temperature of the cooling water and - Gas flow rate of the sample.
Chapter 13 ___________________________________________________________Recording Data CHAPTER 13 RECORDING DATA This chapter provides instructions on data recording with the DM500. Data Recording You can record measurement data and view the recorded data on the display. 1. Open MENU: press 2. Select ►Recording/Viewing, press 3. Select ►Record data, press 4. Select Interval, press 5. Set the measurement interval by selecting the interval time by using the arrow buttons, press SELECT.
User's Guide ______________________________________________________________________ Interval 5s 15 s 30 s 1 min 5 min 15 min 30 min 1 hour 3 hours 12 hours Max. recording duration (memory full) 68 min 3h 6h 13 h 68 h 8d 17 d 34 d 102 d 409 d Stopping Recording 1. Open MENU: press . 2. Select ►Recording/Viewing, press 3. Select ►Record data, press 4. To stop recording, select Start/Stop recording and press 5. Now you can go and see the recorded file by selecting . . STOP. SHOW.
Chapter 13 ___________________________________________________________Recording Data 2. Select ►Recording/Viewing, press . 3. Select Memory status, press SHOW to see the amount of memory in use and the estimated free space. 4. To return to the main view, press OK and EXIT. Deleting All Record Files The data memory can be cleared as follows: 1. Open MENU: press . 2. Select ►Recording/Viewing, press 3. Select Clear data memory, press CLEAR. Press deletion of all recorded data files. 4.
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Chapter 14 _________________________________________________________ Output Interfaces CHAPTER 14 OUTPUT INTERFACES This chapter describes the serial communication settings and outputs of the DM500.
User's Guide ______________________________________________________________________ CAUTION The dip switches behind the DMI500 MUST NOT be touched, because the processor may be destroyed as a result of false dip switch positions. NOTE Before connecting a PC to DMI500 or DMP501, make sure there is no ground potential difference between PC and the DM500. Serial Communication Settings Connect the DM500 to PC by using a serial cable (provided). When connecting EIA-232 (RS232), use the port called 'SERIAL'.
Chapter 14 _________________________________________________________ Output Interfaces 3. Select ►Communications, press . 4. Select Comm. mode, press 5. Select one of the following mode, press SET. SELECT: STOP: Outputs measurements only by command. All commands can be used. RUN: Outputs measurements automatically in a format set by a serial command FORM. Only serial command S can be used. POLL: Outputs measurements only with the serial command SEND.
User's Guide ______________________________________________________________________ The port connections are as follows: pin 1: ch+ (+VDC supply voltage) pin 2: ch- (-VDC supply voltage) pin 3: test (for service use only) pin 4: shield When using 12V loop voltage, the resistance must be less than 90 ohms. An approximate can be calculated by following formula: Rmax = (Vloop - 10V)/20mA You can scale the output to any output range.
Chapter 14 _________________________________________________________ Output Interfaces WAIT: output is enabled when dewpoint measuring status is WAIT All the modes selected: output activity is not dependent on any measurement status. None of the modes selected (never): output is not enabled (invalid output). You can select any combination to control the output. 12. Select Invalid output to set the output reading when the output is not enabled.
User's Guide ______________________________________________________________________ 7. Select Active below: xx, press SET. Set the value below which you want the relay to be released. Use the numeric buttons. Press OK. When the measured value is in between the above and below values, the relay is passive. When choosing lower value as above value and higher value as below value the relay is passive when the measured values is not between the set values.
Chapter 14 _________________________________________________________ Output Interfaces All the modes selected: relay function is not dependent on any measurement mode. None of the modes selected (never): relay function is disabled. You can select any combination of the measurement status. Example: If you want to have relays working on the basis of the STOP and ERR mode to know when the measurement data is not valid, delete the setpoints and select enabled when: STOP and ERR mode. 11.
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Chapter 15 _________________________________________________Calibrationd and Adjustment CHAPTER 15 CALIBRATIOND AND ADJUSTMENT This chapter provides you with information about the calibration and adjustment of the DM500. General About Calibration and Adjustments Calibration Interval The DMP501 dewpoint sensing unit is fully calibrated as shipped from factory. The recommended calibration interval is one year.
User's Guide ______________________________________________________________________ Calibrating DM500 Equipped with a Pump If you have the DM500 with a pump, ensure that the sample flow rate from the humidity generator is sufficient. See the following example: Open outlet (with diffusion coil) Humidity generator Reference instrument 1 splm Gas flow > 3 slpm 1 splm DM500 Figure 22 Gas Flow Rate from the Humidity Generator Making an Adjustment DMP501 needs 4...
Chapter 15 _________________________________________________Calibrationd and Adjustment 6. Turn the service switch 4 to ON-position (adjustment enabled), see page 18, Figure 4, DMP501 back panel, service switches. 7. Open MENU: press 8. Select ►Settings, press 9. Select ►Adjustments, press 10. Select ►Dewpoint adjustments, press 11. Press SET. Give the reference value (Ref.) by using the numeric buttons. Then, give the measured value (Meas.). Press OK. 12.
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Chapter 16 _____________________________________________________ Serial Line Commands CHAPTER 16 SERIAL LINE COMMANDS The DM500 detector is operated via a serial line by using suitable terminal software like Windows Hyper Terminal (see also MI70-link). The serial output interface is RS232.Connect the RS232 cable to the connector on the back panel of the DMI500 user interface unit. The serial cable can also be connected to the back panel of the DMP501 sensing unit.
User's Guide ______________________________________________________________________ Setting commands SERI UNIT TIME RSEL ASEL AERR COOLER* FLOW* XFLOW* PRES* XPRES* TP* XTP* Setting the serial communication parameters Setting the units Setting the date and time Setting the relays Setting and scaling the analog outputs Setting the invalid output value for the analog channel Setting the cooling method status Setting the flow value Setting the flow value temporarily Setting the pressure Setting the pressure
Chapter 16 _____________________________________________________ Serial Line Commands command R does not change the default operation mode set with the command SMODE. Example: >r 0.000 'C slpm 0.000 'C slpm 0.00 'C 0.00 hPa 0.00 0.00 'C 0.00 hPa 0.00 S Stopping the Continuous Output Syntax: S Type S to stop outputting. ADDR Setting the Device Address Syntax: ADDR xx where xx = 0...99 (address) The address is used in POLL mode when more than one device is connected to one serial line.
User's Guide ______________________________________________________________________ Example: >intv 1 min Output interval: > 1 MIN FORM Defining the Output Format Syntax: FORM [amount of decimals] [quantity] [u] [status] [date][time] [addr] With the FORM command you can determine the output form of commands R and SEND.
Chapter 16 _____________________________________________________ Serial Line Commands [quantity] Type one or several of the following quantities: TD/ TDF/ H2O/PW/RH/TW/A/ANTP/X/H/DT/T/P/FLOW/+TDF/ +TD/+PW TD = dewpoint temperature TDF = dewpoint/frostpoint temperature H2O = humid air volume/dry air volume PW = water vapour partial pressure RH =relative humidity TW =wet-bulb temperature A = absolute humidity A = absolute humidity in NTP conditions X = mixing ratio H = enthalpy DT = difference of T and Td/f
User's Guide ______________________________________________________________________ OUTPUT MODIFICATION FIELDS [text field] Type the text you want inside the quotation marks "text". [/] Type / to return the factory setting of FORM command. Only alone, without any other specifiers. [ASCII character] Type \xxx where xxx is a three digit decimal number of the character, for example \035 outputs the # character.
Chapter 16 _____________________________________________________ Serial Line Commands 3. Output needed: Relative humidity and pressure to be shown with a unit. The fields are separated with " " marks. Carriage return and line feed in the end. >form 2.1 rh " " u " " 2.4 p " " u \r \n 2.1 RH " " U " " 2.4 P " " U \r \n >send 23.0 % 1.0164 bar Operational Commands START Starting the Measurement Syntax: START Starts the dewpoint measurement and activates the cooling system.
User's Guide ______________________________________________________________________ HEAT Starting/Stopping the Optional Heater Syntax: HEAT ON/OFF Example: >heat Heat > >heat on Heat > >heat off Heat > : OFF : ON : OFF SALT Enables/Disables the Salt Contamination Detection Syntax: SALT ON/OFF [interval] Default: SALT ON Example: >salt Salt sensing > : OFF 24 : ON 24 Salt sensing is off. >salt on Salt sensing > Salt sensing is on and detection interval is 24 h.
Chapter 16 _____________________________________________________ Serial Line Commands SCAL Starts the Salt Detection Limit Determination Cycle Syntax: SCAL The determination of the salt detection limit can take several minutes. Please also see page 65 for more information about salt detecting. Example: >scal Salt limit > : 0.36280 PTEST Starts the Cooling Capacity Test Syntax: PTEST During the test device reports the sensor temperature.
User's Guide ______________________________________________________________________ ANAL Starts/Stops the Statistical Filtering Syntax: ANAL ON/OFF Type command ANAL ON to turn off the statistical filtering. Command ANAL OFF turns on the statistical filtering. See section Statistical Filtering on page 61 for more information.
Chapter 16 _____________________________________________________ Serial Line Commands Setting Commands SERI Setting the Serial Communication Parameters Syntax: SERI [baud] [parity] [bits] [stops] [duplex] where [baud] = [parity] [bits] [stops] [duplex] = = = = 300/600/1200/2400/4800/9600/19200/38400/57600/1 15200 N (none)/E (even)/O (odd) 7 (7 bits)/ 8 (8 bits) 1 (1 stop bit)/2 (2 stop bits) H(half-duplex)/F (full-duplex) The current settings are output if you give the command without the paramet
User's Guide ______________________________________________________________________ NOTE When you want to have both metric and non-metric temperature units (C/F) for different quantities, select the units with keypad. The serial command UNIT changes all temperature units either to metric or non-metric.
Chapter 16 _____________________________________________________ Serial Line Commands Select the quantity, setpoints and hysteresis and set the criteria for enabling the function. See more about the relays from page 77.
User's Guide ______________________________________________________________________ Use the following quantity abbreviations: TDF/TD/H2O/RH/PW/TW/A/ANTP/X/H/DT/T/P/FLOW/+TDF/ +TD/+PW Enabling criteria keywords: OFF STOP ERR OK WAIT ON relay is never enabled (inactive) relay is enabled when dewpoint measuring status is STOP relay is enabled when dewpoint measuring status is ERR relay is enabled when dewpoint measuring status is OK relay is enabled when dewpoint measuring status is WAIT relay is always enab
Chapter 16 _____________________________________________________ Serial Line Commands Example: >aerr Ch1 error Ch2 error Ch3 error >aerr ? Ch1 error Ch2 error Ch3 error > out out out : : : 4 4 4 out out out : : : 20 20 20 mA ? 20 mA ? 20 mA ? 20 mA mA mA COOLER Setting the Cooling Method Status Syntax: COOLER [WATER/AIR] Example: >cooler Cooler > >cooler water Cooler > >cooler air Cooler : AIR : WATER : AIR FLOW Setting the Flow Value Syntax: FLOW Sets the flow value in current unit sel
User's Guide ______________________________________________________________________ XFLOW Setting the Flow Value Temporarily Syntax: XFLOW x.xxx where x.xxx = sample air flow value The function of XFLOW is the same as with the command FLOW except that with the command XFLOW the setting is valid only until power is turned off or the command XFLOW is given without parameters. After this the flow rate stored with the command FLOW is valid again.
Chapter 16 _____________________________________________________ Serial Line Commands The function of XPRES is the same as with the command PRES except that with the command XPRES the setting is valid only until power is turned off or the command XPRES is given without a pressure value. After this the pressure stored with the command PRES is valid again. Example: >pres 1.0231 Pressure: >xpres 5.5 Pressure: >xpres Pressure: > 1.0231 bar 5.5 bar 1.
User's Guide ______________________________________________________________________ The function of XTP is the same as with the command TP except that with the command XTP the setting is valid only until power is turned off or the command XTP is given without parameters. After this the pressure stored with the command TP is valid again. Adjustments In adjustment, the reading of DM500 is changed to correspond to the reference value.
Chapter 16 _____________________________________________________ Serial Line Commands The CDP* command displays also the coefficients of the correction polynomial, as well as the reference value and residual error for each calibration data point. Example: >cdp 1. reference : -39.99 1. measurement : -40.009 2. reference : -30.01 2. measurement : -30.030 3. reference : -20.01 3. measurement : -20.026 4. reference : -9.98 4. measurement : -9.977 5.
User's Guide ______________________________________________________________________ 7. measurement : 19.982 8. reference : 29.98 8. measurement : 29.989 9. reference : 39.98 9. measurement : 39.989 10. reference : Reference Measurement -39.990 -40.009 -30.010 -30.030 -20.010 -20.026 -9.980 -9.977 0.000 -0.006 10.000 10.002 19.990 19.982 29.980 29.989 39.980 39.
Chapter 16 _____________________________________________________ Serial Line Commands 4. Set the temperature sensor to the second reference conditions. Wait until the reading is stabilized. 5. Press any key and give the value of the second reference, press ENTER. Tp : OK > 20.0000 2. ref ? 80 FCAL Adjusting the Flow Meter (in one point) Syntax: FCAL 1. Turn the switch 4 (see Figure 4 on page 18, service switches) to ON-position to enable the adjustment.
User's Guide ______________________________________________________________________ Others ? Outputting the Device Settings Syntax: ? ?? Outputting the Device Settings in POLL-State Syntax: ?? DEL Deleting the Data Files Syntax: DEL [file] where file = NOTE 1...
Chapter 16 _____________________________________________________ Serial Line Commands HELP Outputting the Commands Syntax: HELP Example: >help Available commands: ADDR CLOSE COOLER FLOW ICE OPEN PRES PUMP R SALT SNUM START STOP TIME TP ECHO ALARM ASEL SERI FORM ERRS ? DIR HELP INIE INTV SEND SMODE UNIT VERS DEL PLAY INIE Reverting the Factory Settings Syntax: INIE Does not affect calibration, date, time or data file memory.
User's Guide ______________________________________________________________________ commands OPEN addr and SEND addr can be used. The transmitter does not echo in POLL mode. OPEN & CLOSE Opening and Closing the Lines Syntax: OPEN x where x = 0...99 (address of the device) Syntax: CLOSE In STOP-mode: command OPEN has no effect, CLOSE sets the transmitter in POLL-mode. In POLL-mode: command OPEN sets the transmitter temporarily in STOP-mode, command CLOSE returns the device to POLL-mode.
Chapter 16 _____________________________________________________ Serial Line Commands SCC Sensor Circuit Check Syntax: SCC ON/OFF xx where xx = checking interval (h) Example: >scc Sensor check >scc on 8 Sensor check : ON 6 : ON 8 SSC Sensor Status Check Syntax: SSC ON/OFF xx where xx = checking interval (s) Sets the transient recovery time (or disables transient recovery). Turns the transient recovery ON/off.
User's Guide ______________________________________________________________________ VERS Outputting the Program Name and Version Syntax: VERS >vers DMI500 / 1.25 DMP501 / 1.
Chapter 17 ________________________________________________________ Mi70 Link Program CHAPTER 17 MI70 LINK PROGRAM This chapter provides instructions on using the DM500 together with the MI70 Link Program and a personal computer. Installation 1. Connect the MI70 link cable between your PC and DM500's SERIAL port (on the back panel of the DMI500). 2. Go to the DM500 menu, select ►Interfaces, ►Communications, Com.mode: MI70 Link. 3. Insert the CD-ROM into your CD-ROM drive.
User's Guide ______________________________________________________________________ Displayed Quantities When downloading recorded data or using the real-time window, the quantities and units are determined by the current selections in the DM500's "Quantities and units" menu at downloading time. Measurement uncertainty values are shown in own data table columns after quantities Td/f, Td and Pw (if some of these quantities are active).
Chapter 18 _____________________________________________________________ Maintenance CHAPTER 18 MAINTENANCE This chapter provides information that is needed in basic maintenance of the product. Cleaning the Sensor Clean the sensor whenever the system gives a warning of contamination on the sensor. Cleaning is also strongly recommended before calibration and adjustment or when there is a reason to believe that the measurement is unstable or the offset has increased.
User's Guide ______________________________________________________________________ 1. 2. Remove the sensor cap. 1. Turn off the measuring mode; the sensor must not be cooled. 2. Loosen the three Allen screws of the sensor cap with an Allen key. (Note that the screws have retainers, they do not come off completely). 3. Remove the sensor cap. 4. Take a rectangular piece of soft, clean paper tissue (optical or clean room grade tissue).
Chapter 18 _____________________________________________________________ Maintenance Error Messages Error Message Interpretation and Action Please check that the cooling air/water temperatures and flows are correct, see chapter Setting up for Operation, page 35. Check that cooling method (air/water) setting is correct, page 60. In case of constant error, please contact Vaisala, see page 19.
User's Guide ______________________________________________________________________ Please contact Vaisala, send the device for repair, page 19. Clock battery failure. Please contact Vaisala, send the device for repair, page 19. Please contact Vaisala, send the device for repair, DMI500 selftest "C/D/F/L" failed. Let page 19. the service check the device. *Errors marked with* are shown only in the error history log.
Chapter 18 _____________________________________________________________ Maintenance - What was connected to the product and to which connectors? - Input power source type, voltage and list of other items (lighting, heaters, motors etc.) that were connected to the same power output. - What was done when the failure was noticed? 4. Include a detailed return address with your preferred shipping method on the Problem Report. 5.
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Chapter 19 ____________________________________________________________ Specifications CHAPTER 19 SPECIFICATIONS This chapter provides the technical data of the product. Measured Variables Dewpoint Temperature DM500S (standard) DM500H (high) DM500X (extended) -40...+60 ºC Td -60...+60 ºC Td -75...+60 ºC Td The upper limit value is with heating option only. Without a heating option, limited to ambient temperature. Standard calibration up to + 18 ºC Td.
User's Guide ______________________________________________________________________ 0.4 Deviation temperature [°C] 0.3 Specifications + 0.2 Calibration uncertainty (+2s) 0.1 Repeatability (+2s) 0 Repeatability (-2s) -0.1 Calibration uncertainty (-2s) -0.2 Specifications - -0.3 -0.4 -80 -70 -60 -50 -40 -30 -20 -10 0 10 20 Dew / Frostpoint [°C] Figure 23 Dewpoint Temperature Measurement Repeatability Response time (see the following graph) Time to ±0.
Chapter 19 ____________________________________________________________ Specifications External Temperature (Optional) Sensor Pt100RTD DIN IEC 751 class ¼B Measurement range -40...+80 ºC Typical accuracy at +20 ºC ±0.1 ºC Typical temperature dependence of electronics 0.001 ºC Cable length 2 m/5 m/10 m Integrated Pressure (Optional) for ppmv calculations Measurement range Accuracy 0...2 bar or 0... 20 bar ±1.
User's Guide ______________________________________________________________________ Wetted parts' materials Housing classification Mechanical piping connections Storage temperature range Weight Stainless steel (AISI 316L), silicone elastomer, Vectra LCP, tantalum, quartz IP31 (NEMA 2) Swagelok 6 mm/ /¼" -40...
Chapter 19 ____________________________________________________________ Specifications Options for DMI500 Configurable alarm relays 60 VDC (42 V Peak)/0.75 A Handle for portable model Front panel for rack installations Outputs Digital EIA-232 (RS232) serial output RS485 serial output Analog outputs (optional, three channels) Operating voltage ccuracy at +20 ºC (typical) Temperature dependence 4...20 mA passive 12...28 V ±0.05% full scale 0.
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Chapter 19 ____________________________________________________________ Specifications VAISALA ______________________________________________________________________ 125
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Appendix A __________________________________________________________ Humidity Theory APPENDIX A HUMIDITY THEORY This Appendix provides you with a basic explanation of the terms related to humidity theory that are used in many parts of this manual. Measured and Calculated Results of DM500 DM500 measures the dewpoint temperature of a gas by condensing water on a surface and using SAW technology to detect this condensation.
User's Guide ______________________________________________________________________ There are many ways of expressing the water vapor content of a gas. Some water vapor quantities, such as dewpoint temperature, can be measured directly and fundamentally. Other parameters, such as relative humidity, require knowledge of additional information, such as the temperature of the gas. Saturation Vapor Pressure Saturation vapor pressure is the maximum pressure of water vapor that can exist at a given temperature.
Appendix A __________________________________________________________ Humidity Theory Partial Pressure of Water Vapor (Pw) Partial pressure of water vapor refers to the part of the overall pressure exerted by the water vapor component of a gas. Note that the partial pressure of water vapor can be calculated when the dewpoint temperature of a gas is known. Pw = A ⋅10( m⋅Td /(Td +Tn )) (2) Likewise, dewpoint temperature can be calculated for a given partial pressure of water vapor.
User's Guide ______________________________________________________________________ in air at that particular temperature. It is defined below as the ratio of the water vapor pressure Pw to the saturation water vapor pressure Pws.
Appendix A __________________________________________________________ Humidity Theory Absolute Humidity (a) Absolute humidity (a) is the mass of water vapour present in unit volume of moist air of a given temperature and pressure. a = 2.16679 ⋅ Pw T + 273.15 (6) where T = a = Pw = temperature (ºC) absolute humidity (g/m3) water vapor pressure Absolute Humidity at NTP (aNTP) a = 2.
User's Guide ______________________________________________________________________ h = T ⋅ (1.01 + 0.00189 ⋅ x) + 2.5 ⋅ x (9) where x T h = = = mixing ratio (g/kg) temperature (ºC) enthalpy Humid Air Volume/Dry Air Volume PPMv Parts per million (PPM) by volume is the ratio of the partial pressure of the water vapor to the partial pressure of dry gas.
Appendix A __________________________________________________________ Humidity Theory Response Time – The response time of a hygrometer is proportional to the amount of water vapor in the gas being measured. Thus, at dewpoint temperatures of –60°C, things take ten times longer than at – 40° because there is ten times less water vapor.
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