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Related Manuals for Vaisala Drycap DMT142
Summary of Contents for Vaisala Drycap DMT142
- Page 1 USER'S GUIDE Vaisala DRYCAP® Dewpoint Transmitter DMT142 M210397EN-D...
- Page 2 The contents are subject to change without prior notice. Please observe that this manual does not create any legally binding obligations for Vaisala towards the customer or end user. All legally binding commitments and agreements are included exclusively in the applicable supply contract or Conditions of...
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Page 3: Table Of Contents
Regulatory Compliances ............8 Electromagnetic Compatibility..........8 Trademarks ................8 Warranty ..................9 CHAPTER 2 PRODUCT OVERVIEW.................. 3 Introduction to Dewpoint Transmitter DMT142 ..... 3 The Basic Features and Options ..........3 CHAPTER 3 FUNCTIONAL DESCRIPTION............... 5 ® Advanced DRYCAP Technology ........... - Page 4 Serial Line Output Commands ..........26 Start Measurement Output ..........26 Stop Measurement Output ..........26 Set Output Interval...............26 Polling Mode for DMT142 Transmitter........27 Set Transmitter Address............27 Set Serial Interface Mode ............27 OPEN Opening the Transmitter in POLL-State....28 SEND Outputting a Reading Once........28 CHAPTER 6 MAINTENANCE....................29...
- Page 5 Wiring of Voltage Output Version..........9 Figure 4 Wiring of Current Output Version ..........9 Figure 5 Pin Order of DMT142 Connector (Transmitter Side) ....10 Figure 6 Snap-On Type Cable..............11 Figure 7 Screw Fitting Type Cable ............11...
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Page 7: Chapter 1 General Information
- Chapter 3, Functional Description, describes the advanced functionality of Dewpoint Transmitter DMT142, including the auto-calibration, sensor purge and sensor warming functions. - Chapter 4, Installation, provides you with information that is intended to help you install Dewpoint Transmitter DMT142. VAISALA_________________________________________________________________________ 5... -
Page 8: Version Information
User's Guide _______________________________________________________________________ - Chapter 5, Serial Commands, contains the operating instructions for the serial interface of Dewpoint Transmitter DMT142. - Chapter 6, Maintenance, provides information that is needed in basic maintenance of Dewpoint Transmitter DMT142, and contact information for Vaisala Service Centers. -
Page 9: General Safety Considerations
Product Related Safety Precautions The Dewpoint Transmitter DMT142 delivered to you has been tested for safety and approved as shipped from the factory. Note the following precautions: Do not modify the unit. Improper modification can damage the CAUTION product or lead to malfunction. -
Page 10: Recycling
Dispose of batteries and the unit according to statutory regulations. Do not dispose of with regular household refuse. Regulatory Compliances Vaisala DRYCAP® Dewpoint Transmitter DMT142 complies with the following performance and environmental test standards: Electromagnetic Compatibility EN 61326-1:1997 + Am1:1998, Electrical equipment for measurement, control and laboratory use - EMC requirements - Industrial environment. -
Page 11: Warranty
Products should Vaisala so require, be sent to the works supplied hereunder, which obligations of Vaisala or to such other place as Vaisala may liabilities are hereby expressly cancelled and indicate in writing, freight and insurance waived. Vaisala's liability... - Page 12 User's Guide _______________________________________________________________________ This page intentionally left blank. 2 ____________________________________________________________________ M210397EN-D...
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Page 13: Chapter 2 Product Overview
The DMT142 transmitter is easy to install and the mechanics have been designed for harsh environments requiring protection against dust, dirt and splashed water. -
Page 14: Figure 1 Dewpoint Transmitter Dmt142 Components
User's Guide _______________________________________________________________________ - RS232 serial line connection for service use with DMT142RS cable. - Optional sampling cells with different installation options available as DMT142 installation accessories. 0507-093 Figure 1 Dewpoint Transmitter DMT142 Components The following numbers refer to Figure 1 above: Serial line connector (for service use) ®... -
Page 15: Functional Description
The self-diagnostic procedures that are conducted are called auto-calibration, sensor purge and sensor warming. Auto-Calibration The auto-calibration feature of the DMT142 transmitter is an automatic procedure which greatly reduces the possible drift in the dry end of the dewpoint measurement. It is performed at one hour intervals, and when the power is switched on. -
Page 16: Sensor Purge
Sensor Warming in High Humidities Additionally the DMT142 transmitter has a warming feature which prevents the sensor and filter from becoming wet in high humidities. High humidity may be present when the dewpoint temperature rises close to the gas temperature. -
Page 17: Chapter 4 Installation
This chapter provides you with information that is intended to help you install Dewpoint Transmitter DMT142. Selecting Location In the mounting of Dewpoint Transmitter DMT142 it is important that the point of installation represents well the gas to be measured. Temperature changes do not affect the dewpoint measurement, but pressure changes will have an effect on the measurement. -
Page 18: Figure 2 Mounting Dewpoint Transmitter Dmt142
Figure 2 Mounting Dewpoint Transmitter DMT142 The numbers in the following list refer to Figure 2 above: Select a proper location to mount the DMT142 and remove the yellow sensor protective cap. Fit the sealing washer onto the probe. Mount the transmitter to the measurement point. The transmitter has parallel thread G1/2"... -
Page 19: Wiring
Chapter 4 ________________________________________________________________ Installation Wiring Table 3 Wiring Table Pin Number Wire Colour Name (in supplied cables EN50044) Brown + VDC supply voltage White - analog output signal sense (voltage output versions only) Blue - VDC supply voltage Black + analog output signal 12-28V 0507-095 Figure 3... -
Page 20: Optional Connection Cable
0507-097 Figure 5 Pin Order of DMT142 Connector (Transmitter Side) Optional Connection Cable DMT142 is delivered optionally with two types of connection cables, snap-on type or with screw fitting/locking. Table 4 Description of DMT142 Connection Cable Property Description / Value... -
Page 21: Power Supply Requirements
Figure 7 Screw Fitting Type Cable Power Supply Requirements The DMT142 transmitters are designed to operate with a supply voltage of 12 ... 28 VDC (voltage output version) or 18 ... 28 VDC (current output version). When measuring in pressures 20 ... 50 bar (290 ... -
Page 22: Figure 8 Example Of Sensor Purge Current (At Room Temperature With 24 Vdc)
User's Guide _______________________________________________________________________ 150 mA ↓ Duration 60 seconds 500 ms/div 0507-098. 0507-099 Figure 8 Example Of Sensor Purge Current (at Room Temperature with 24 VDC) Typical duty cycle. Sensor purge current varies with supply voltage and operating temperature. The peak value is the highest in the lowest temperature. -
Page 23: Mounting
Max 50 bar 0507-102 Figure 10 DMT142 Installed Directly to Pipeline In addition, due to the small size of DMT142 you can use a standard G1/2" T-shaped pipe fitting (not available from Vaisala) when installing DMT142 into a pipeline. VAISALA________________________________________________________________________ 13... -
Page 24: Sampling From Pressurized Processes
0.2 l/min is recommended. The DMT142 is very light in weight which means that it can be installed in a sample pipeline in the sampling cells without the need of any additional mechanical support. -
Page 25: Dmt242Sc2 Sampling Cell With Swagelok Connectors
DSC74 Sampling Cell with Quick Connector and Leak Screw Vaisala DSC74 sampling cell allows quick and easy connection of the transmitter into pressurized processes. The quick connector allows the transmitter to be plugged in to the pipeline in seconds. The leak screw maintains the process pressure in the sampling cell but allows a small flow through the sampling cell. -
Page 26: Figure 13 Dsc74 Sampling Cell With Accessories
User's Guide _______________________________________________________________________ 0507-105 Figure 13 DSC74 Sampling Cell with Accessories The following numbers refer to Figure 13 above: Thread adapter type 3/8"G-1/2"G Thread adapter type 3/8"G-1/4"G Quick connector Leak screw Sampling cell DMT242SC When using the DSC74, seal the threads of the quick connector or thread adapter carefully with PTFE thread seal tape. -
Page 27: Dsc74B Two-Pressure Sampling Cell
Chapter 4 ________________________________________________________________ Installation DSC74B Two-Pressure Sampling Cell The DSC74B can be used as the DSC74 for measurements in process pressure. DSC74B limits the flow rate with a leak screw. The maximum flow can also be increased by removing the leak screw and adjusting the flow manually with the valve. -
Page 28: Dsc74C Two-Pressure Sampling Cell With Coil
User's Guide _______________________________________________________________________ DSC74C Two-Pressure Sampling Cell with Coil The DSC74C is mechanically like the DSC74B, but it is supplied with a coil for measurements in atmospheric pressure. The coil can also be used as a cooling coil for sampling from high temperature processes. 0510-034 Figure 16 Default Assembly of DSC74C... -
Page 29: Figure 17 Alternative Assembly Of Dsc74C (For Tight Spaces)
Chapter 4 ________________________________________________________________ Installation 0403-113 Figure 17 Alternative Assembly of DSC74C (for Tight Spaces) The following numbers refer to Figure 17 above: Gas comes out Coil Thread, max. size 7 mm Gas goes in Valve The thread size cannot exceed 7 mm. Use the provided adapter to avoid damage to the probe. -
Page 30: Dm240Fa Duct Installation Flange
0510-035 Figure 18 DM240FA with DMT142 Numbers refer to Figure 18 above: Measured gas DMT142 transmitter DM240FA flange (thread G1/2" ISO) Recommended additional hole (plugged) for T field check reference measurement probe (for example, Vaisala DM70) 20 ___________________________________________________________________ M210397EN-D... -
Page 31: Chapter 5 Serial Commands
This chapter contains the operating instructions for the serial interface of Dewpoint Transmitter DMT142. Connecting Serial Interface The use of the DMT142 via the serial bus requires a DMT142 serial interface cable (Vaisala order code: DMT142RS). Connect the serial cable between your PC and DMT142 serial port. -
Page 32: Commands For Basic Settings
User's Guide _______________________________________________________________________ Commands for Basic Settings Select Nonmetric Unit The DMT142 Transmitter outputs dewpoint temperature T in either Celsius or Fahrenheit degrees depending on the unit selection. Syntax: UNIT n<cr> Select Metric Unit Syntax: UNIT m<cr> Scale Dewpoint Analog Output Syntax: ASCL x yy zz<cr>... -
Page 33: Set Analog Output Mode
Even though the software of the transmitter supports two channels, NOTE the transmitter only has one analog output channel (channel 0). The output mode of channel 1 is always set to 0 in the AMODE command syntax. DMT142 Firmware Version Output Syntax: VERS<cr> Example: >vers DMTS142C / 1.01 >... -
Page 34: Pressure Compensation
Pressure Compensation In pressurized environments, in order to optimize the accuracy of the DMT142, the actual process pressure can be set to the DMT142 if the pressure setting is not configured when ordering the product. In a worst case scenario, an incorrect pressure setting may result in an additional uncertainty of 1.5 °C in the dewpoint measurement. -
Page 35: Test Analog Output Current
Chapter 5 ___________________________________________________________Serial Commands Test Analog Output Current The operation of the analog current output can be tested by forcing the output to a given value which can then be measured with a current meter from the analog output. Syntax: ITEST aa.aaa x<cr> where aa.aaa current (mA) -
Page 36: Serial Line Output Commands
User's Guide _______________________________________________________________________ Serial Line Output Commands Start Measurement Output The transmitter outputs continuous measurement values as an ASCII text string to the PC. Syntax: R<cr> Example: >r 58.289 23.051 14.424 58.276 23.058 14.426 58.278 23.035 14.406 where in the first column: relative humidity (%RH) in the second column: ambient temperature (°C or °F) in the third column: dewpoint (°C or °F) Outputting the results continues in intervals issued with the command... -
Page 37: Polling Mode For Dmt142 Transmitter
When set to POLL state, the transmitters communicate one at a time when the specific transmitter address is called on the serial line. Note that using the DMT142 serial output requires the DMT142RS serial line cable. Set Transmitter Address Syntax: ADDR n<cr>... -
Page 38: Open Opening The Transmitter In Poll-State
User's Guide _______________________________________________________________________ OPEN Opening the Transmitter in POLL-State Syntax: OPEN nn<cr> where address (0 ... 99) Resulting (only in POLL-state): >DMT nn line opened for operator commands<CR> = ASCII 7 ( CTRL-G ) SEND Outputting a Reading Once Syntax: SEND<cr> Syntax in POLL-state: SEND nn<cr>... -
Page 39: Chapter 6 Maintenance
Dewpoint Transmitter DMT142, and contact information for Vaisala Service Centers. Calibration and Adjustment The DMT142 is fully calibrated as shipped from factory. The recommended calibration interval is 2 years. However, calibration should be done if there is a reason to believe that device is not within the accuracy specifications. -
Page 40: Vaisala Service Centers
User's Guide _______________________________________________________________________ A dirty or corroded filter may cause increased response times. In case the DMT142 transmitter is used in a drying system with silica gel (or other drying agent) the dust from the dryer may collect on the sensor slowing the response but also generating a micro climate around the sensor altering the dewpoint at the sensor. -
Page 41: Chapter 7 Troubleshooting
RESET command on the serial line. If the source of error is not found and the transmitter does not return to the normal state with the reset, please contact Vaisala Instruments Service or local Vaisala representative, see section Vaisala Service Centers on page 30. - Page 42 User's Guide _______________________________________________________________________ This page intentionally left blank. 32 ___________________________________________________________________ M210397EN-D...
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Page 43: Chapter 8 Technical Data
Chapter 8 _____________________________________________________________ Technical Data CHAPTER 8 TECHNICAL DATA This chapter provides the technical data of Dewpoint Transmitter DMT142. Specifications Table 7 Measured Variable Property Description / Value Dewpoint temperature Measurement range -80 ... +60 °C (-112 ... +140 °F) T... -
Page 44: Figure 19 Dmt142 Dewpoint Measurement Accuracy Graph
User's Guide _______________________________________________________________________ 0610-073 Figure 19 DMT142 Dewpoint Measurement Accuracy Graph Table 8 Operating Environment Specifications Property Description / Value Temperature 0 … +60 °C (+32 ... +140 °F) Relative humidity 0 ... 100 %RH Pressure 0 ... 50 bar (0 ... -
Page 45: Table 10 General Specifications
Chapter 8 _____________________________________________________________ Technical Data Table 10 General Specifications Property Description / Value ® Sensor Vaisala DRYCAP 180D Measured gases noncorrosive gases (SF6 gas with special model) Recommended calibration interval to 2 years confirm the specified accuracy Operating voltage with current output 18 ... -
Page 46: Spare Parts And Accessories
User's Guide _______________________________________________________________________ Spare Parts and Accessories Order Code Description 211598 M8 output cable 2 m with snap-on locking (IEC 60947-5-2) HMP50Z032 Shielded M8 output cable 0.32 m with thread locking HMP50Z300 Shielded M8 output cable 3 m with thread locking HMP50Z500 Shielded M8 output cable 5 m with thread locking... -
Page 47: Dimensions In Mm (Inches)
Chapter 8 _____________________________________________________________ Technical Data Dimensions in mm (inches) 0507-107 Figure 20 DMT142 Dimensions Wiring Quick Reference Wiring of the connector VDC supply + (brown) signal sense – (voltage output only) (white) VDC supply – (blue) signal + (black) 0507-097... - Page 50 *M210397EN*...