Vaisala DMP248 Operating Manual
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Vaisala DMP248 Operating Manual

Vaisala DMP248 Operating Manual

Dewpoint transmitter
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DMP248 Dewpoint
Transmitter
OPERATING
MANUAL
M210492
-
EN
A
J
2003
ULY

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Summary of Contents for Vaisala DMP248

  • Page 1 DMP248 Dewpoint Transmitter OPERATING MANUAL M210492 2003...
  • Page 2 Finland Visit our Internet pages at http://www.vaisala.com/ © Vaisala 2003 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.

  • Page 3: Table Of Contents

    ................................1 AFETY ................................. 1 ARRANTY CHAPTER 2 PRODUCT DESCRIPTION ......................3 ..........................3 ENERAL CHARACTERISTICS DMP248....................... 4 HE OPERATING PRINCIPLE OF THE Use in high pressure............................6 CHAPTER 3 INSTALLATION........................... 7 ......................7 ELECTING THE PLACE OF INSTALLATION ..........................7 OUNTING THE TRANSMITTER Mounting;...
  • Page 4 OPERATING MANUAL _______________________________________________________________ Using LED commands ..........................64 CHAPTER 7 MAINTENANCE .........................67 ..........................67 EFERENCE MEASUREMENTS ............................67 DIAGNOSTICS ..............68 EMPERATURE CHANNEL ADJUSTMENT WITH SIMULATORS ................70 EASUREMENT OF OUTPUT CURRENTS USING TEST POINTS ......................71 DJUSTING THE CONTRAST OF THE DISPLAY ..........................71 AISALA ERVICE ENTERS CHAPTER 8 TECHNICAL DATA ........................72 ............................72...

  • Page 5: Chapter 1 General Information

    Note highlights important information. It calls attention to an essential procedure, practice, condition or the like. Warranty Vaisala issues a guarantee for the material and workmanship of this product under normal operating conditions for one (1) year from the date of delivery. Exceptional operating conditions, damage due to careless handling and misapplication will void the guarantee.

  • Page 7: Chapter 2 Product Description

    The dewpoint output can be scaled freely, for example, dewpoint -40...+20 °C can be set to correspond to 0...1 V. The DMP248 transmitter has two analogue outputs and can be connected to a serial bus via the RS 232C interface or optionally through an RS 485/422 serial module or a current loop module.

  • Page 8: The Operating Principle Of The Dmp248

    The offset calibration algorithm incorporated into the DMP248 transmitter uses the fact that the capacitance of a thin film polymer sensor is proportional to RH as seen in formula 1.
  • Page 9 0.35% RH to get the correct value of 0.55% RH. shows the DRYCAP sensor as mounted on a DMP248 IGURE probehead. Through a combination of the polymer sensor and Pt 100...

  • Page 10: Use In High Pressure

    The DRYCAP sensor mounted on a DMP248 probe. IGURE Note that the auto-calibration takes place only if the DMP248 is used in ambient humidities below 10 %RH (dewpoint below -12 C at 20 C) and at ambient temperature 0...+80 °C.

  • Page 11: Chapter 3 Installation

    In hot and dirty processes, a sample system can also be used. Mounting the transmitter , you can see the dimensions of the IGURE IGURE DMP248 transmitter: __________________________________________________________________________ 7 AISALA...
  • Page 12 OPERATING MANUAL _______________________________________________________________ ø6.5 Dimensions of the DMP248 electronics housing (in IGURE mm). NOTE 1. Always mount the transmitter housing with the cable bushings pointing downwards to ensure IP65 (NEMA4) rating 2. Make sure that the connection cable has the right thickness 7...10 mm) and that the cable bushing is carefully tightened.

  • Page 13: Mounting; Overview

    3 _______________________________________________________________ HAPTER INSTALLATION NOTE Take care not to damage the pipe of the probe. If the pipe is damaged, the probe head is less tight and it will not go through the clasp nut. Mounting; overview fitting body parallel thread hex = 24mm G1/2 ISO 228/1 tapered thread...

  • Page 14: Mounting The Probe Directly To The Process

    OPERATING MANUAL _______________________________________________________________ NOTE Be careful not to tighten the clasp nut more than 60 as this may result in difficulties when trying to open it. The probe is delivered with non-leaking screw A mounted. For by- pass measurements, this screw is removed and replaced with leaking screw B (included) and an O-ring is placed on the groove of the sintered filter prior to installation.

  • Page 15: Installing The Probe Through The Ball Valve Assembly

    3 _______________________________________________________________ HAPTER INSTALLATION If the sensor head is installed in a pressurized chamber, always make sure that the pressure of the chamber is equalized with the ambient pressure prior to removing the probe. capped nut DIN 917-M22x1.5 when the probe is pulled out for maintenance, cap sealing the hole with a capped nut;...
  • Page 16 OPERATING MANUAL _______________________________________________________________ probe non-leaking screw A handle >30 mm ball of the ball valve (hole diameter at least 14 mm) process pipe / chamber Installing the sensor head through the DMP248BVS IGURE ball valve assembly. NOTE The probe can be installed in the process through the ball valve assembly provided that the process pressure is less than 10 bars.
  • Page 17 3 _______________________________________________________________ HAPTER INSTALLATION STEP 1: mount the probe with the ball valve assembly closed; tighten the clasp nut manually. bushing R1/2 cone/G1/2(40 bar) e.g. Camozzi 2520-1/2-1/2 clasp nut (the bushing serves for moving the probe (sinter) to such a distance from the fitting body ball valve that the valve R1/2 cone, sealed...
  • Page 18 OPERATING MANUAL _______________________________________________________________ STEP 2: open the ball valve assembly. manual press tool probe pipe ø5.5 marking groove fitting ferrule clasp nut handle (hex 27 mm) fitting body leak screw (B) (hex. 24 mm) (hex. 1.5 mm) ø14 O-ring ball of the ball valve DRYCAP®...
  • Page 19 3 _______________________________________________________________ HAPTER INSTALLATION STEP 3: push the probe head through the ball valve assembly into the process. If the pressure is high, use a manual press tool. Note that the sensor head must be pushed so deep that the filter is completely inside the process flow.
  • Page 20 OPERATING MANUAL _______________________________________________________________ gas escape channel: use this position for NOTE by-pass measurements keep the marking groove in sight when leak screw (B) O-ring using leak screw (B) sintered filter DRYCAP® sensor process pipe or chamber Installing the sensor head for by-pass measurements. 3-11 IGURE When pushing the probe head through the ball valve assembly, be...

  • Page 21: Mounting The Probe With A Quick Connect

    3-12 IGURE DMP248 probe. The chamber can be made of stainless steel AISI 316. keep the marking groove in sight when using...

  • Page 22: Sample Cell

    It may be necessary to use the sample cell if the process (e.g. a pipe) is too small for the DMP248 sensor head. Furthermore, if the process is very hot (>80 °C) or particularly dirty, the probe is installed in a sample cell behind a cooling coil and/or filter.
  • Page 23 3 _______________________________________________________________ HAPTER INSTALLATION process pipe metal G1/4 plate thickness e.g. 228/1 3mm (1/8") AISI 316 thread M6 or 1/4"-20 UNC metal G1/4 hose screw clamp FRONT VIEW TOP VIEW Dimensions of the metal plate Fastening to a process pipe with the help of a metal 3-15 IGURE plate...

  • Page 24: Grounding

    OPERATING MANUAL _______________________________________________________________ Grounding A single electrical cable with a screen and three to ten wires is recommended for power and analogue output/serial bus connections. The cable diameter should be 7...10 mm. The screen of the electrical cable must be grounded properly to achieve best possible EMC performance.
  • Page 25 3 _______________________________________________________________ HAPTER INSTALLATION insert the wires into the transmitter housing through the gland tighten the nut connect the wires into the screw terminals and fasten a cable tie around the wires cable tie transmitter housing gland brass disks rubber ring When the cable is grounded as explained, the metallic parts of the NOTE sensor head, the screen of its cable, the transmitter housing and the...

  • Page 26: Connections

    CURRENT/VOLTAGE OUTPUTS POWER SUPPLY (INTERNAL OR EXTERNAL) Do not use power supply ground (-) as output signal ground OPENED COVER OF THE DMP248 Electrical connections 3-17 IGURE Power supply 24 VDC 24 VAC (see Chapter Connection to an AC supply) Output signals 0...20 mA...

  • Page 27: Connection To An Ac Supply

    HAPTER INSTALLATION Connection to an AC supply The DMP248 transmitter can also be connected to an AC supply without an external rectifier. However, when more than one transmitter is connected for example to one 24 VAC transformer, a common loop is formed and there is an increased risk of a short- circuit.

  • Page 29: Chapter 4 Commissioning

    COMMISSIONING COMMISSIONING CHAPTER 4 When the DMP248 transmitter leaves the factory, its measurement ranges and output signals have already been selected. The user can subsequently change the measurement units between metric and non- metric and select and scale the output signals with software functions, see Chapter Selecting and scaling the analogue output quantities and Appendix 1.

  • Page 30: Selecting The Analogue Outputs

    OPERATING MANUAL _______________________________________________________________ Selecting the analogue outputs The DMP248 transmitter can be ordered ready with the current or voltage outputs required. If the outputs need to be changed, move the jumpers in connector X15 into positions as shown in IGURE...
  • Page 31 ð Scale". All jumpers are used only with the 0...1 V outputs. When other out- puts are in use, the spare jumpers are kept in connector X55. spare jumpers OPENED COVER OF THE DMP248 Spare jumpers IGURE _________________________________________________________________________ 27...

  • Page 32: Connecting The Rs 232C Serial Bus

    OPENED COVER OF THE DMP248 Serial bus connections. IGURE To connect a PC to the DMP248 transmitters via the RS 232C serial bus, one of the following cables is required. The type of cable depends on the terminal and the connector type.
  • Page 33 The processor does not allow the following combinations: no parity, 7 data bits, 1 stop bit: if this combination is given the DMP248 programme will change the number of stop bits to 2. even or odd parity, 8 data bits, 2 stop bits: if this combination is given the programme changes the number of stop bits to 1.

  • Page 34: Reverting To Factory Settings Of The Serial Port

    To minimize the possibility of these interferences, always use the same main outlet (same phase of the main electricity) for the PC and the power supply of DMP248. It is always preferable to use the connector instead of the connector X17 because it is more immune to interferences.
  • Page 35 4 _____________________________________________________________ HAPTER COMMISSIONING transmitter is reset; if the jumper is in place when power is turned on, the transmitter does not work. After jumper insertion the transmitter is in STOP mode, ready to receive commands. The same method is used when the transmitter is in POLL mode and the user has forgotten its address.

  • Page 37: Chapter 5 Commands

    COMMANDS COMMANDS CHAPTER 5 The DMP248 transmitter uses a microprocessor; therefore, its configuration can be set according to the user's needs. This is done through commands, either utilizing the menus on the local display or giving commands through the serial interface (see Appendix 1). Most often, the commands are used to change the settings of the two analogue channels.

  • Page 38: Led Commands

    LEDs DOWN press switches OPENED COVER OF THE DMP248 Location of press switches and LEDs IGURE Use the up and down switches (marked with arrows on the printed board) to find the desired command code and acknowledge it with the ENT switch.

  • Page 39: Display/Keypad Commands

    5 ________________________________________________________________ HAPTER COMMANDS Display/keypad commands Display mode In the display mode, the transmitters output measurements on the display; different quantities can be scrolled with the arrow keys. The first line is scrolled with button and the second line with button ; all selections are stored with ENTER.
  • Page 40 OPERATING MANUAL _______________________________________________________________ With some commands (e.g. calibration) the figures are changed using the arrow keys. When an arrow key is pressed continuously for a while, the numbers start changing at an increasing rate. Auto-calibration NOTE Normally auto-calibration parameters do not have to be changed. Select More in the main menu and then again More in the second More menu.
  • Page 41 5 ________________________________________________________________ HAPTER COMMANDS This parameter defines the measuring time of the change in dewpoint prior to the auto-calibration (see the parameter Max dTdp). If the setting is correct, press ENT. If the setting needs to be changed, press CL and change the value with arrow keys.

  • Page 42: Analogue Output Commands

    The pressure setting is used for pressure compensation of the DMP248 transmitter. Forced auto-calibration Select More in the main menu and then again More in the second More menu.

  • Page 43: Selecting And Scaling The Analogue Output Quantities

    5 ________________________________________________________________ HAPTER COMMANDS If the settings are correct, press ENT. If the settings need to be changed, press CL: the quantity (mA/V) starts flashing; it can be changed with the arrow keys and acknowledged with the ENT key the lower limit starts flashing acknowledge the lower limit with ENT or start changing it by pressing CL;...

  • Page 44: Serial Bus Settings

    OPERATING MANUAL _______________________________________________________________ Select Scale. The quantity and scaling for channel 1 are displayed: If the settings are correct, press ENT. If the settings need to be changed, press CL: the quantity starts flashing; it can be changed with the arrow keys and acknowledged with the ENT key the lower limit starts flashing acknowledge the lower limit with ENT or start changing it by...
  • Page 45 Selecting stop bits: Full duplex/half duplex: The processor does not allow the following combinations: no parity, 7 data bits, 1 stop bit: if this combination is given the DMP248 programme will change the number of stop bits to 2 _________________________________________________________________________ 41 AISALA...

  • Page 46: Setting The Transmitter Address

    OPERATING MANUAL _______________________________________________________________ even or odd parity, 8 data bits, 2 stop bits: if this combination is given the programme changes the number of stop bits to 1 NOTE The serial bus settings become effective only after reset. Setting the transmitter address Address is used when more than one transmitter is connected to one serial bus;...

  • Page 47: Output Modes

    The output modes only affect output through the serial interface: the transmitter accepts all display and LED commands irrespective of which serial output mode it is in. The DMP248 transmitter has three serial output modes: RUN, STOP and POLL. In the RUN state the transmitter outputs measurements automatically through the serial interface to a PC or a peripheral.

  • Page 48: Pressure Compensation

    OPERATING MANUAL _______________________________________________________________ The output interval setting can be changed as follows: press CL the number starts flashing if the interval needs to be changed, press CL again and enter the new interval; otherwise press ENT the unit (s, min, h) starts flashing the unit can be changed with the arrow keys and acknowledged with ENT after this the programme returns to Mode menu...

  • Page 49: Setting The Date

    5 ________________________________________________________________ HAPTER COMMANDS If the pressure needs to be changed, press CL; enter the new pressure with the arrow keys The pressure compensation takes place only with the security lock NOTE jumper connected. If the security lock jumper is not connected, the pressure compensation is performed with the value 1013.25 hPa.

  • Page 50: Serial Commands

    More detailed descriptions of the serial commands can be found in Appendix 1. Here only the most commonly used command sequences are described. The instructions on how to connect the DMP248 transmitters to serial bus are given in Chapter Connecting the RS 232C serial bus.
  • Page 51 5 ________________________________________________________________ HAPTER COMMANDS The interval parameter defines the frequency of auto-calibration cycles. When the transmitter is turned on, the first auto-calibration takes place after on hour unless the frequency has been set to less than an hour. After the first auto-calibration, the set frequency is activated and the auto-calibration takes place e.g.
  • Page 52 The pressure setting is used for pressure compensation of the DMP248 transmitter. The pressure is given in hPa/mbar; for converting pressure units, see Appendix 8.

  • Page 53: Analogue Outputs

    5 ________________________________________________________________ HAPTER COMMANDS Analogue outputs Setting the analogue outputs Disconnect the security lock jumper! AMODE a bb.bbb cc.ccc d ee.eee ff.fff <cr> = channel 1: = voltage output = current output bb.bbb = lower limit of channel 1 cc.ccc = upper limit of channel 1 = channel 2: = voltage output...

  • Page 54: Scaling The Analogue Outputs

    OPERATING MANUAL _______________________________________________________________ channel 1's quantity channel 2's quantity (RH, T, Td, ppm) Example: dewpoint temperature selected on channel 1 and temperature on channel 2 >ASEL T <cr> ( Td -50.00 'C ? -40<cr> ( Td 10.00 'C 0<cr> 10.00 'C 0<cr>...

  • Page 55: Stopping The Measurement Output

    5 ________________________________________________________________ HAPTER COMMANDS Stopping the measurement output S<cr> Ends the RUN mode; after this command all other commands can be used. Outputting the reading once SEND <cr> in STOP mode SEND aa <cr> in POLL state = address of the transmitter when more than one transmitter is connected to a serial bus (0...99) Output: Td= -9.3 'C PPM=...
  • Page 56 The processor does not allow the following combinations: no parity, 7 data bits, 1 stop bit: if this combination is given the DMP248 programme will change the number of stop bits to 2 even or odd parity, 8 data bits, 2 stop bits: if this combination is...

  • Page 57: Resetting The Transmitter

    5 ________________________________________________________________ HAPTER COMMANDS Resetting the transmitter RESET <cr> Operating the transmitter via the serial bus Setting the serial interface SMODE xxxx<cr> xxxx = STOP, RUN or POLL In STOP mode: measurements output only command, commands can be used In RUN mode: outputting automatically, only command S can be used In POLL mode: measurements output only with command SEND.
  • Page 58 OPERATING MANUAL _______________________________________________________________ Example: relative humidity calibration is performed at transmitter 2 which is in POLL state opens the line to transmitter 2 >OPEN 2 <cr> calibration started >CRH <cr> line closed >CLOSE <cr> 54_____________________________________________________________________M210492...

  • Page 59: Chapter 6 Calibration And Adjustment

    NOTE To achieve the best accuracy in low dewpoints, the DMP248 shall be sent once a year to Vaisala Service Centers for dewpoint calibration and adjustment.

  • Page 60: Two-Point Calibration And Adjustment Adjustment Procedure

    OPERATING MANUAL _______________________________________________________________ When LED commands are used and when the two analogue channels do not output either relative humidity and/or temperature, relative humidity is calibrated on channel 1 and temperature is calibrated on channel 2. The calibration ranges are 0...100 %RH and -20...+80 °C. When the transmitter is calibrated at two points, the points must be either 50 %RH or 50 C apart from each other.

  • Page 61: Using Display/Keypad Commands

    6 ______________________________________________ AND ADJUSTMENT HAPTER CALIBRATION RH : 11.5 Ref1 ? 11.3 <cr> Press any key when ready... Place the sensor head in the calibration hole of the NaCl bottle (wet end reference) in the humidity calibrator. Wait for 30 minutes. Press any key and enter the second point value and press <cr>.

  • Page 62: Using Led Commands

    OPERATING MANUAL _______________________________________________________________ If necessary, change the second point reading with the arrow keys and press ENT. Using LED commands Leave the calibrator and the transmitter for at least 4 hours in the same space so that their temperatures have time to equalize. Remove the filter cap on the transmitter.

  • Page 63: Humidity Calibration Table

    6 ______________________________________________ AND ADJUSTMENT HAPTER CALIBRATION Humidity calibration table Greenspan's calibration table ABLE Temperature °C °F LiCl 11.3 11.3 11.3 11.3 4...20 mA 5.81 5.81 5.81 5.81 0...20 mA 2.26 2.26 2.26 2.26 0...1 V 0.113 0.113 0.113 0.113 0...5 V 0.565 0.565 0.565...

  • Page 64: Using Display/Keypad Commands

    OPERATING MANUAL _______________________________________________________________ Check the transmitter against the reference. Give command CT <cr>, enter the first point value and press <cr>: >CT <cr> xx.x Ref1 ? yy.y <cr> Press any key when ready If you want to see how the sensor stabilizes to the reference temperature, enter c <cr>...

  • Page 65: Two-Point Temperature Calibration And Adjustement

    6 ______________________________________________ AND ADJUSTMENT HAPTER CALIBRATION Connect an ammeter/voltmeter to the analogue outputs (connector X2). Give command ¡¡l¡. At the first calibration point the LED on the left flashes; adjust the first point (offset) with the arrow switches to the same reading with the reference and press ENT switch.

  • Page 66: Using Display/Keypad Commands

    OPERATING MANUAL _______________________________________________________________ The stabilization of the sensor can be monitored well by entering c <cr> instead of the reference value. Using display/keypad commands Leave the reference instrument and the transmitter for at least 4 hours in the same space so that their temperatures have time to equalize.

  • Page 67: Calibration Of The Analogue Outputs

    6 ______________________________________________ AND ADJUSTMENT HAPTER CALIBRATION Check that the reading corresponds with the reading of the reference instrument. If not, adjust the second point. If necessary, adjust with the arrow switches to the correct value and press ENT. At the second calibration point the second LED from the left flashes.

  • Page 68: Using Led Commands

    OPERATING MANUAL _______________________________________________________________ Enter the measured lower end current/voltage on channel 1. Enter the measured upper end current/voltage on channel 1. Connect the meter to the output of channel 2 and enter the measured lower end current/voltage on channel 2. Enter the measured upper end current/voltage on channel 2.
  • Page 69 6 ______________________________________________ AND ADJUSTMENT HAPTER CALIBRATION the LED on the left flashes; set the low end of channel 2 with the arrow keys and press ENT the second LED from the left flashes; set the high end of channel 2 with the arrow keys and press ENT The analogue outputs are calibrated to ensure that outputs are correctly scaled: for example, when the output is scaled to 4...20 mA,...

  • Page 71: Chapter 7 Maintenance

    The reference measurement should be made as close to the checked sensor as possible and the readings should be read at the same time, when possible. A re-calibrated DMP248 transmitter can be used as a reference. Self-diagnostics The DMP248 transmitter goes through a self-diagnostics procedure when the power is switched on.

  • Page 72: T Emperature Channel Adjustment With P T 100 Simulators

    OPERATING MANUAL _______________________________________________________________ ERRS <cr> If there are no error messages, only a prompt is displayed: >ERRS <cr> > When errors have occurred, the transmitter outputs the error code (see Appendix 5 for all error messages): >ERRS <cr> ( all ) out of range >...

  • Page 73: Adjustment Using Serial Commands

    7 ____________________________________________________________MAINTENANCE HAPTER Adjustment using serial commands Give command CT and enter the first point value and press <cr>: >CT <cr> xx.x Ref1 ? yy.y <cr> Press any key when ready Set the Pt 100 simulator at the highest temperature to be calibrated, and press any key.

  • Page 74: Measurement Of Output Currents Using Test Points

    CH1 + OPENED COVER OF THE DMP248 Location of the CH1 and CH2 test points IGURE 70_____________________________________________________________________M210492...

  • Page 75: Adjusting The Contrast Of The Display

    The contrast of the display can be adjusted using the trimmer "LCD display contrast" located next to the press switches. Vaisala Service Centers NORTH AMERICAN SERVICE CENTER Vaisala Inc., 100 Commerce Way, Woburn, MA 01801-1068, USA. Phone: +1 781 933 4500, Fax +1 781 933 8029 Email: us-customersupport@vaisala.com EUROPEAN SERVICE CENTER Vaisala Instruments Service, Vanha Nurmijärventie 21 FIN-01670 Vantaa,...

  • Page 76: Chapter 8 Technical Data

    TECHNICAL DATA CHAPTER 8 Measured variables Dewpoint temperature Measurement range -60...+80 °C (below 0 °C DMP248 outputs frostpoint) Dewpoint accuracy ± 2 °C (-50...+80 C) (see figure below) Measurement range and accuracy. IGURE Response time (90%) at flow rate 0.08 m/s (1 bar) at 20 °C:...

  • Page 77: Outputs

    8 ____________________________________________________________ HAPTER TECHNICAL DATA Temperature Measurement range -40...+80 °C for specified Td accuracy 0...+80 C Typical accuracy of electronics at +20 °C (+68 °F) ±0.1 °C Typical temperature dependence of electronics 0.005 °C/°C Temperature sensor Pt 100 IEC 751 1/3 Class B Relative humidity Measurement range 0...100 %RH...

  • Page 78: General

    OPERATING MANUAL _______________________________________________________________ General Sensor DRYCAP S sensor Connections screw terminals, 0.5 mm wires (AWG 20), stranded wires recommended Operating voltage 24 VDC/ isolated VAC (20...28 V) 115 VAC/230 VAC with power supply module Power consumption 100 mA maximum (24 VDC) Recommended external load for current outputs <500...

  • Page 79: Electronics

    8____________________________________________________________ HAPTER TECHNICAL DATA Sensor head dimensions: PROBE P R O B E U P ø5.5 PUSHED cable length DOWN 2, 5 or 10 m adjustment R1/2 range120 mm ISO 7/1 R1/2 ISO 7/1 ø13.5 Weight of display cover 420 g Electronics User interface 3 keys and 4 LEDs inside the...

  • Page 80: Electromagnetic Compatibility

    OPERATING MANUAL _______________________________________________________________ Electromagnetic compatibility The DMP248 transmitter fulfills the standard EN 61326-1:1997 +Am 1:1998 + Am 2:2001, Electrical equipment for measurement, control and laboratory use - EMC requirements; Industrial environment. Test methods Emission Radiated emissions CISPR16 class B (CISPR22 Class B)

  • Page 81: Chapter 10 Spare Parts And Accessories

    10 _______________________________________________ HAPTER SPARE PARTS AND ACCESSORIES SPARE PARTS AND CHAPTER 10 ACCESSORIES Order code Description 16452SP Sintered filter, stainless steel ® DRYCAPS DRYCAP S dewpoint sensor HMP230PW Power supply module 5237 Fuse 160 mA T 5x20 mm for power supply module HMP230RS RS 485/422 serial module HMP230CL...

  • Page 83: Appendix 1 Serial Commands

    __________________________________________________________ PPENDIX SERIAL COMMANDS APPENDIX 1 SERIAL COMMANDS APPENDIX 1 CALIBRATION COMMANDS DRYCAL Defining the frequency of auto-calibration cycles DCAL Forced auto-calibration NALOGUE OUTPUT COMMANDS AMODE Setting the analogue outputs ASEL Selecting the scaling the analogue output quantities ASCL Scaling the analogue outputs ALIBRATION COMMANDS Relative humidity calibration Temperature calibration...

  • Page 85: Drycal Defining The Frequency Of Auto-Calibration Cycles

    __________________________________________________________ PPENDIX SERIAL COMMANDS Auto-calibration commands DRYCAL Defining the frequency of auto-calibration cycles DRYCAL<cr> >drycal DCAL ON Interval min : 60 ? Max dTdp: 2.00 ? dTdp time s : 10 Max corr. : 0.040 ? Settl time s : 50 The interval parameter defines the frequency of auto-calibration cycles.

  • Page 86: Dcal Forced Auto-Calibration

    __________________________________________________________ PPENDIX SERIAL COMMANDS DCAL Forced auto-calibration DCAL<cr> >dcal Calibration... any key to abort > (appears when the auto-calibration is completed, max. 60 - 70 seconds) If you press any key, the calibration is interrupted. If no key is pressed, the calibration takes place immediately. The text above is displayed during the calibration.
  • Page 87 __________________________________________________________ PPENDIX SERIAL COMMANDS >AMODE U 0 1 U 2 10 <cr> Ch1 : 0.000 ... 1.000 V Ch2 : 2.000 ... 10.000 V The current settings can be checked by giving the command without any parameters: >AMODE <cr> Ch1 : 0.000 ... 20.000 mA Ch2 : 0.000 ...

  • Page 88: Ascl Scaling The Analogue Outputs

    __________________________________________________________ PPENDIX SERIAL COMMANDS The outputs and their scales can also be given directly with the ASEL command. ASEL xxx yyy aaa.a bbb.b ccc.c ddd.d <cr> channel 1's quantity channel 2's quantity aaa.a lower limit of channel 1 bbb.b upper limit of channel 1 ccc.c lower limit of channel 2 ddd.d...

  • Page 89: Calibration Commands

    __________________________________________________________ PPENDIX SERIAL COMMANDS Calibration commands Relative humidity calibration Disconnect the security lock jumper! CRH <cr> With this command the transmitters can be calibrated against two RH references. Two-point calibration is performed using saturated salt solutions in controlled conditions according to the following instructions: >CRH <cr>...

  • Page 90: Acal Calibrating The Analogue Outputs

    __________________________________________________________ PPENDIX SERIAL COMMANDS In one-point offset correction, the Ref2 prompt is acknowledged with <cr>: >CT <cr> 0.80 Ref1 ? 0.0 <cr> Press any key when ready ... 75.50 Ref2 ? <cr> If the stabilization of the sensor to the temperature of the calibrator or the ref- erence needs to be monitored, the measurement output can be repeated by giv- ing command c<cr>...

  • Page 91: Output Via The Serial Bus

    __________________________________________________________ PPENDIX SERIAL COMMANDS Entering linear correction coefficients Disconnect the security lock jumper! LI <cr> The LI command is one way of calibrating the transmitters. >LI <cr> offset : 0.000 -.6 <cr> gain : 1.000 ? <cr> offset : 0.000 ? <cr>...

  • Page 92: Send Outputting A Reading Once

    __________________________________________________________ PPENDIX SERIAL COMMANDS Stopping the measurement output S<cr> Ends the RUN state; after this command all other commands can be used. SEND Outputting a reading once SEND <cr> in STOP state SEND aa <cr> in POLL state address of the transmitter when more than one transmitter is connected to a serial bus (0...99;...

  • Page 93: Echo Turning The Serial Interface Echo On/Off

    __________________________________________________________ PPENDIX SERIAL COMMANDS ERRS Outputting error messages ERRS <cr> During operation error messages are not output automatically through the se- rial interface. If there is any reason to doubt that there is something wrong with the transmitter, possible error messages can be output with command ERRS. If there are no error messages, only a prompt is displayed: >ERRS <cr>...

  • Page 94: Form Setting The Output Format

    __________________________________________________________ PPENDIX SERIAL COMMANDS When this is changed into 10 minutes, the command is: >INTV 10 <cr> Output intrv. : 10 min The unit is changed into seconds with: >INTV S <cr> Output intrv. : 10 s The change can also be done with one command: >INTV 10 S <cr>...
  • Page 95 __________________________________________________________ PPENDIX SERIAL COMMANDS Any text can be written in the command and it appears in the output. For ex- ample: RH: \UUU.U\ T: \+TT.TT\\r RH: 54.0 T: +25 <cr> The format can be deleted by giving \ as a parameter: Note.
  • Page 96 __________________________________________________________ PPENDIX SERIAL COMMANDS Inactivating the time output >ftime off Form. time >r RH= 19.4 %RH T= 26.1 'C RH= 19.8 %RH T= 26.1 'C RH= 20.6 %RH T= 26.1 'C RH= 20.5 %RH T= 26.1 'C RH= 19.9 %RH T= 26.1 'C RH= 19.6 %RH T= 26.1 'C FDATE Adding date to output...

  • Page 97: Seri Serial Bus Settings

    600 N 8 1 FDX The processor does not allow the following combinations: no parity, 7 data bits, 1 stop bit: if this combination is given the DMP248 programme will change the number of stop bits to 2 even or odd parity, 8 data bits, 2 stop bits: if this combination is given the...

  • Page 98: Reset Resetting The Transmitter

    __________________________________________________________ PPENDIX SERIAL COMMANDS metric units non-metric units °C °F For example, the command for setting the non-metric units is: >UNIT N <cr> Output units : non metric When the command is given with no parameters, the transmitter outputs the currently valid setting.
  • Page 99 __________________________________________________________ PPENDIX SERIAL COMMANDS Operation modes SMODE Setting the serial interface SMODE xxxx<cr> xxxx STOP, RUN or POLL In STOP mode: measurements output only by command, all commands can be used In RUN mode: outputting automatically, only command S can be used In POLL mode: measurements output only with command SEND.

  • Page 100: Itest Testing The Analogue Outputs

    __________________________________________________________ PPENDIX SERIAL COMMANDS >OPEN 2 <cr> <cr><lf> 'DMP nn line opened for operator commands' <cr><lf><lf><bel> >CRH <cr> >CLOSE <cr> <cr><lf> 'line closed' <cr><lf> Others ITEST Testing the analogue outputs ITEST <cr> ITEST a b <cr> current/voltage of channel 1 current/voltage of channel 2 The operation of the analogue outputs can be tested by forcing the outputs to given values which can then be measured with a current/voltage meter from...
  • Page 101 The pressure setting is used for pressure compensation of the DMP248 transmitter. The pressure also strongly effects the ppm value. The pressure is always given in hPa/mbar; for pressure conversion, see Appendix 8.

  • Page 102: Date Setting The Date

    __________________________________________________________ PPENDIX SERIAL COMMANDS XPRES Setting the pressure for pressure compensation and for ppm calculations temporarily XPRES pppp.pp <cr> pppp.pp = absolute pressure (hPa) The function and format of XPRES are the same as those of the PRES command except that by using XPRES, the setting is valid only until a reset is given, or power is turned off or pressure is set to zero using XPRES.

  • Page 103: Outputting The Transmitter Settings

    When the current time is asked, the new time is passed with <cr>. VERS Name and version of the programme VERS <cr> For example: >VERS <cr> DMP248 / x.yy where x.yy is the programme version. Outputting the transmitter settings ? <cr> For example: >? <CR>...

  • Page 104: Outputting The Transmitter Settings Also In Poll Mode

    __________________________________________________________ PPENDIX SERIAL COMMANDS ?? Outputting the transmitter settings also in POLL mode ?? <cr> Command ?? outputs the same information as command ? but it works also when the transmitter has been set to POLL mode. However, if there are more than one addressed transmitters connected to the serial bus, they all will respond at the same time and the output on the screen will be chaotic.

  • Page 105: Appendix 2 Power Supply Module

    2 ________________________________________________________________________ PPENDIX APPENDIX 2 POWER SUPPLY MODULE APPENDIX 2 ..............................101 ..........................102 OWER SUPPLY MODULE Installing the power supply module ......................102 ..........................103 ECHNICAL SPECIFICATIONS Setting and activating the outputs using an RS line ................... 134 ________________________________________________________________________ 101 AISALA...

  • Page 106: Appendix

    2_________________________________________________________________________ PPENDIX Power supply module Installing the power supply module The mains power connection may be connected to the power supply module only by an authorized electrician. A readily accessible disconnect device shall be incorporated in the fixed wiring (IEC 950). Remove the plastic plug in the transmitter housing and replace it with the cable gland.

  • Page 107: Technical Specifications

    Do not detach the power supply module from the transmitter when the power is on. WARNING Do not connect the power supply to mains when it is not installed in a DMP248 transmitter. Technical specifications Operating voltage 115 VAC (93...127 V) 230 VAC (187...253 V)

  • Page 109: Appendix 3 Installing And Using The Rs 485/422 Serial Port Module

    3 ________________________________________________________________________ PPENDIX APPENDIX 3 INSTALLING AND USING THE RS 485/422 SERIAL PORT MODULE APPENDIX 3 ..............................105 ..............................106 NSTALLATION ..............................106 PERATION ..........................108 ETWORK CONFIGURATION Single loop operation ..........................108 Dual loop operation............................ 110 ..................112 HECKING THE SERIAL PORT NETWORK OPERATION STOP mode..............................

  • Page 110: Appendix

    The module is plugged in connectors X4 and X5 on the main board of the DMP248 transmitter; connector X1 on the module board to connector X4 and connector X2 to connector X5.
  • Page 111 3 ________________________________________________________________________ PPENDIX connection can be used. No address is needed when only one DMP248 transmitter is used; when several transmitters are connected to the same line, each transmitter must be given an address in the initial configuration. A single transmitter can get its operating voltage from the master or it can have its own (floating) power supply or it has the power supply module in use.

  • Page 112: Network Configuration

    3_________________________________________________________________________ PPENDIX The RS 485/422 module has separate lines for transmitting and receiving, but they can be connected together with jumpers. Dual loop connection is the factory setting; when a single loop connection is used, the positions of jumpers in connector X4 on the module must be changed.
  • Page 113 3 ________________________________________________________________________ PPENDIX Connect wires to the transmitter's serial connector. Check the wiring. The following procedure must be repeated with all transmitters. Open the transmitter cover. Pull out the RS 485/422 serial port module, if it is already mounted. Set the serial port of the terminal to 4800 baud, even parity, seven data bits and one stop bit, full duplex (4800 E 7 1 FDX).

  • Page 114: Dual Loop Operation

    3_________________________________________________________________________ PPENDIX NOTE The transmitter outputs no prompt (>) after the SMODE POLL command and it only reacts to commands which include its address. Check that the transmitter responds to its address: >send 22 Td= -47.4 'C T= 29.1 'C Disconnect the terminal.
  • Page 115 3 ________________________________________________________________________ PPENDIX RS 232C port of the terminal to connector X17 on the top of the main board and switch the power on. When dual loop is used, the jumpers in connector X4 on the module board must be as shown below. Set the address of the transmitter, it can be any number between 1 and 99.

  • Page 116: Checking The Serial Port Network Operation

    3_________________________________________________________________________ PPENDIX >send 22 RH= 24.4 %RH T= 29.1 'C Disconnect the terminal. Check that the jumpers in connector X4 are in the right places. Remount the RS 485/422 serial module. Close the cover. Repeat this setting procedure with each transmitter. When all transmitters on the network have been configured, switch them off.

  • Page 117: Poll Mode

    3 ________________________________________________________________________ PPENDIX Use command ? to find out the settings of the active transmitter: ? <cr> DMP248 / 1.01 CPU serial nr : Keyboard type : Address Output units metric Baud P D S 4800 E 7 1 FDX...

  • Page 118: Rs 485 Network Settings

    Line feed after carriage return HDX/FDX When terminal is set to general <lf> (line feed) after <cr> (carriage return), the listings will have two line feeds when also the DMP248 transmitters send line feed. Specifications Connections Berg sockets on the main board screw terminals 0.5 mm²...

  • Page 119: Appendix 4 Installing And Using The Current Loop Module

    4 ________________________________________________________________________ PPENDIX APPENDIX 4 INSTALLING AND USING THE CURRENT LOOP MODULE ............................ 116 NSTALLATION ............................116 PERATION ........................ 118 ETWORK CONFIGURATION Single loop operation........................118 Single loop wiring ........................119 Dual loop operation ........................120 Dual loop wiring........................... 121 ................

  • Page 120: Appendix

    The module is plugged in connectors X4 and X5 on the main board of the DMP248 transmitter; connector X1 on the module board to connector X4 and connector X2 to connector X5.
  • Page 121 The serial line structure is a serial interfaced chain (daisy chain). At one end of the serial line there must be a DMP248 transmitter and at the other end a line master. A branch line can be made with a junction box.

  • Page 122: Network Configuration

    Data transmission is achieved by switching the loop current on and off. Normally, current flows through the loop(s) even when the DMP248 transmitter is not on, so switching one transmitter off does not affect the other transmitters on the loop.

  • Page 123: Single Loop Wiring

    4 ________________________________________________________________________ PPENDIX Set the serial port of the terminal to 4800 baud, even parity, seven data bits and one stop bit, full duplex (4800 E 7 1 FDX). The serial settings of the transmitter must also be 4800 E 7 1 FDX and the transmitter must be in STOP mode.

  • Page 124: Dual Loop Operation

    4_________________________________________________________________________ PPENDIX Check that the transmitter responds to its address: send 22 Td= -47.4 'C T= 29.1 'C Disconnect the terminal. Remount the digital current loop module. Close the cover. When all transmitters on the network have been configured, switch them off. Dual loop operation Single pair/dual pair use is configured through wiring (see figure on page 2).

  • Page 125: Dual Loop Wiring

    4 ________________________________________________________________________ PPENDIX Dual loop wiring Set the address of the transmitter, it can be any number between 1 and 99. In this example the address is 22: >addr 22 Address Set the serial bus settings according to your system. This setting will become valid after next RESET or power off: >seri 2400 e 7 1 f 2400 E 7 1 FDX...

  • Page 126: Checking The Serial Port Network Operation

    4_________________________________________________________________________ PPENDIX Checking the serial port network operation Normally, measurement readings are asked when the transmitter is in POLL mode; then the command must include the address of the transmitter. If the settings of the transmitter need to be changed, the transmitter is switched to STOP mode with command OPEN;...

  • Page 127: Poll Mode

    Line feed after carriage return HDX/FDX When terminal is set to general <lf> (line feed) after <cr> (carriage return), the listings will have two line feeds when also the DMP248 transmitters send line feed. ________________________________________________________________________ 123 AISALA...

  • Page 128: Specifications

    4_________________________________________________________________________ PPENDIX Specifications Galvanic isolation 1500 VAC/DC max. (1 min) Loop supply voltage 40 V max. Loop supply current 20 mA nominal must be current limited Operating loop voltage requirement 4 V/each transmitter (TX+/TX-) on the loop 2 V/each receiver (RX+/RX-) on the loop Loop current 12...30 mA (space)

  • Page 129: Appendix 5 Error Messages

    5 ________________________________________________________________________ PPENDIX APPENDIX 5 ERROR MESSAGES APPENDIX 5 ..............................125 ............................126 RROR MESSAGES Errors after reset............................126 Errors during operation ..........................127 ________________________________________________________________________ 125 AISALA...

  • Page 130: Appendix

    5_________________________________________________________________________ PPENDIX ERROR MESSAGES The DMP248 transmitters go through a self-diagnostics procedure when the power is switched on. When the procedure does not reveal any errors or faults, the transmitter starts operating normally. If errors or faults are found, the transmitter outputs an error message. The error messages can be divided into two groups: error messages after the reset and error messages during operation.

  • Page 131: Errors During Operation

    5 ________________________________________________________________________ PPENDIX ¡l¡¡ CPU EEPROM error l¡¡¡ input hybrid error Errors during operation Two types of errors are possible during operation of the transmitters. The first type indicates that no frequency comes from the converter. Display: Serial bus: E40 f (all ) out of range E41 f (T ) out of range E43 f (Rk1 ) out of range...
  • Page 132 5_________________________________________________________________________ PPENDIX The LEDs display these error types as follows: ¡¡¤¤ no frequency at all ¡¡¤¡ a frequency missing from the RH channel ¡¡¡¤ a frequency missing from the T channel The second error type indicates erroneous y-values (used in internal calculations): Display: Serial bus:...

  • Page 133: Appendix 6 Wiring Diagram

    APPENDIX 6...

  • Page 134: Appendix 7 Alarm Output Unit

    7 ________________________________________________________________________ PPENDIX APPENDIX 7 Alarm output unit The alarm output unit consists of two alarm relays and two opto- isolated outputs (see Figure 1). The relay output 1 is available at screw terminal X1 and the relay output 2 at screw terminal X2. The opto- outputs are activated simultaneously with the corresponding relays and available at screw terminal X5.
  • Page 136 7_________________________________________________________________________ PPENDIX side of the module if the mains power is in use. Attach the ribbon cable from X3 of the alarm unit to the X16 on the main board of the transmitter. NOTE NO jumper in connector X4 during normal operation. When one alarm unit relay is on, the corresponding LED is lit.

  • Page 137: Setting And Activating The Outputs With Menu Commands

    7 ________________________________________________________________________ PPENDIX Setting and activating the outputs with menu commands Disconnect the security lock jumper! Select MORE in the main menu and then ALARM; the following is displayed: If the settings need to be changed, press CL: - the quantity starts blinking; it can be changed with arrow switches, and acknowledged with ENT.

  • Page 138: Setting And Activating The Outputs Using An Rs Line

    7_________________________________________________________________________ PPENDIX Setting and activating the outputs using an RS line Disconnect the security lock jumper! ALARM <cr> ALARM n ON <cr> where n = channel number (1 or 2) The currently valid settings of the alarm output unit can be checked with command ALARM: >alarm<cr>...
  • Page 139 7 ________________________________________________________________________ PPENDIX When the alarm outputs have been set, you can activate the outputs with commands ALARM 1 ON (channel 1) or ALARM 2 ON (channel 2). Note that you can also activate the outputs when giving other parameters with command ALARM. Examples of activating the outputs: with command ALARM: >alarm...

  • Page 141: Appendix 8 Pressure Conversion Chart

    8_________________________________________________________________________ APPENDIX APPENDIX 8 Pressure conversion chart Multiplication factors NOTE: conversions from mmHg and inHg are defined at 0°C and for O and inH O at 4°C. FROM: hPa/mbar PaN/m 0.01 1.333224 mmHg torr 33.86388 inHg 0.09806650 2.490889 1013.25 980.665 1000 68.94757 psia = psi absolute...

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