vaisala GMP343 User Guide
USER'S GUIDE
Vaisala CARBOCAP®
Carbon Dioxide Probe
GMP343
M210514EN-C
PUBLISHED BY
Vaisala Oyj Phone (int.): +358 9 8949 1
P.O. Box 26 Fax: +358 9 8949 2227
FIN-00421 Helsinki
Finland
Visit our Internet pages at http://www.vaisala.com/
© Vaisala 2007
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.
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 Sale.
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Table of Contents
CHAPTER 1
GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
About This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Version Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
General Safety Considerations . . . . . . . . . . . . . . . . . . . . .10
Feedback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
ESD Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
CHAPTER 2
PRODUCT OVERVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Introduction to GMP343 . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
GMP343 Transmitter Components . . . . . . . . . . . . . . . . . . .14
User Configurable CO2 Measurement . . . . . . . . . . . . . . . .15
Principle of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Optics Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Gas Sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Diffusion Sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Flow-Through Sampling . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Sampling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Optional Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Soil Adapter Kits for In-Soil Applications . . . . . . . . . . . . . .19
MI70 Indicator Connection . . . . . . . . . . . . . . . . . . . . . . . . .19
Recharging the Battery Pack. . . . . . . . . . . . . . . . . . . . 19
Structure of the MI70 Indicator . . . . . . . . . . . . . . . . . . 20
Using MI70 as a Display . . . . . . . . . . . . . . . . . . . . . . . 21
Introduction of Function Keys and Menu Structure. 21
Initialization of MI70 . . . . . . . . . . . . . . . . . . . . . . . . 21
Navigation in Menu. . . . . . . . . . . . . . . . . . . . . . . . . 22
Using MI70 in Recording . . . . . . . . . . . . . . . . . . . . . . . 23
Transferring Recorded Data to PC . . . . . . . . . . . . . . . 23
CHAPTER 3
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Wiring of the Junction Box . . . . . . . . . . . . . . . . . . . . . . . . .27
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CHAPTER 4
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Connecting GMP343 to PC . . . . . . . . . . . . . . . . . . . . . . . . . .29
Connection Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Installing the Driver for the USB Cable . . . . . . . . . . . . 29
Opening a Terminal Connection . . . . . . . . . . . . . . . . . . . .30
Operation modes of the GMP343 . . . . . . . . . . . . . . . . . . . . .32
Getting the Measurement Message . . . . . . . . . . . . . . . . . . .33
Measurement Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Starting the Continuous Outputting . . . . . . . . . . . . . . . . . .33
Stopping the Continuous Outputting . . . . . . . . . . . . . . . . .33
Setting the Continuous Outputting Interval . . . . . . . . . . . .34
Outputting the Reading Once . . . . . . . . . . . . . . . . . . . . . . .34
Setting the Serial Interface Measurement Mode . . . . . . . .35
Setting Communication Hardware . . . . . . . . . . . . . . . . . . .35
Serial Communication Settings . . . . . . . . . . . . . . . . . . . . .36
Formatting the Measurement Message . . . . . . . . . . . . . . . .36
Formatting the Message . . . . . . . . . . . . . . . . . . . . . . . . . .36
Setting Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Networking Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Setting the Transmitter Address . . . . . . . . . . . . . . . . . . . . .39
Open and Close . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Setting Echoing Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
Preparation for Network Operation . . . . . . . . . . . . . . . . . .40
Commands during Network Operation . . . . . . . . . . . . . . . .41
Measurement Range, Data Filtering and Linearization . . .41
Setting the Measurement Range . . . . . . . . . . . . . . . . . . . .41
Measurement Data Filtering . . . . . . . . . . . . . . . . . . . . . . . .42
Median Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Averaging Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Smoothing Filter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
How the Filtering Affects the Response Time . . . . . . . 44
Setting the Median Filter . . . . . . . . . . . . . . . . . . . . . . . . . .45
Setting the Averaging Filter . . . . . . . . . . . . . . . . . . . . . . . .45
Setting the Smoothing Filter . . . . . . . . . . . . . . . . . . . . . . . .45
Flushing the Filters (Resynchronization) . . . . . . . . . . . . . .46
Linearization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Setting the Linearization ON/OFF . . . . . . . . . . . . . . . . . . .46
Temperature, Pressure, Relative Humidity, and Oxygen
Compensations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
Temperature Compensation ON/O FF . . . . . . . . . . . . . . . .48
Setting the Oxygen Concentration . . . . . . . . . . . . . . . . . . .49
Setting Oxygen When the Device Is in POLL-mode . . 49
Oxygen Compensation Mode . . . . . . . . . . . . . . . . . . . . . . .49
Setting the Ambient Pressure (hPa) . . . . . . . . . . . . . . . . . .50
Setting Pressure When the Device Is in POLL-mode . 50
Pressure Compensation ON/OFF . . . . . . . . . . . . . . . . . . .51
Setting Ambient Relative Humidity . . . . . . . . . . . . . . . . . . .51
Setting Humidity When the Device Is in POLL-mode. . 51
Relative Humidity Compensation ON/OFF . . . . . . . . . . . .52
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Setting and Testing the Analog Outputs . . . . . . . . . . . . . .52
Analog Output Hardware . . . . . . . . . . . . . . . . . . . . . . . . . .53
Setting the Limit of the Current Output Range . . . . . . . . . .53
Setting the High Limit of the Voltage Output Range . . . . .54
Setting the High Limit of the Concentration Range . . . . . .54
Setting the Low Limit of the Concentration Range . . . . . . .55
Setting the Analog Output Overrange Clip . . . . . . . . . . . . .55
Testing the Analog Output . . . . . . . . . . . . . . . . . . . . . . . . .56
Setting the Analog Output Error Level . . . . . . . . . . . . . . . .56
Device Information and Other General Commands . . . . . .57
Device Information List . . . . . . . . . . . . . . . . . . . . . . . . . . .57
Show the Output Quantities . . . . . . . . . . . . . . . . . . . . . . . .57
Linear and Multipoint Corrections . . . . . . . . . . . . . . . . . . .58
Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58
Command List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59
Showing the Parameters . . . . . . . . . . . . . . . . . . . . . . . . . .59
Software Version Information . . . . . . . . . . . . . . . . . . . . . . .60
Memory Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
Reverting the Factory Parameters . . . . . . . . . . . . . . . . . . .60
Saving the Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
Setting the Optics Heating ON/OFF . . . . . . . . . . . . . . . . . . .61
Resetting the Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . .61
CHAPTER 5
CALIBRATION AND ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
Calibration Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
Factory Calibration and Adjustment . . . . . . . . . . . . . . . . . .64
Calibration and Adjustment by the User . . . . . . . . . . . . . . .64
Calibration (Checking) . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
Checking the Compensations . . . . . . . . . . . . . . . . . . . 64
Measurements in Reference Gases . . . . . . . . . . . . . . 65
Adjustment in 1...2 Points . . . . . . . . . . . . . . . . . . . . . . . . .66
Adjustment in 3...8 Points . . . . . . . . . . . . . . . . . . . . . . . . .67
Example of the 2-Point Adjustment Procedure . . . . . . 67
CHAPTER 6
MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71
Cleaning the Optics (Diffusion Model Only) . . . . . . . . . . . .71
Changing the Filter (Diffusion Model Only) . . . . . . . . . . . .73
Error States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74
Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
Return Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
Vaisala Service Centers . . . . . . . . . . . . . . . . . . . . . . . . . . . .76
VAISALA________________________________________________________________________ 3
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CHAPTER 7
TECHNICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77
Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77
Effects of Temperature, Pressure, Relative Humidity,
and Oxygen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78
Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78
Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79
Humidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79
Oxygen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79
Response time (90 %) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80
Inputs and Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80
Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .81
Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82
Spare Parts and Accessories . . . . . . . . . . . . . . . . . . . . . . . .82
APPENDIX A
DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83
GMP343 (Flow-through) . . . . . . . . . . . . . . . . . . . . . . . . . . . .84
GMP343 (Diffusion) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85
Calibration Cap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86
Mounting Flange . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87
Junction Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88
Mounting Bracket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89
APPENDIX B
LIST OF COMMANDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91
Measurement Commands . . . . . . . . . . . . . . . . . . . . . . . . . . .91
Filtering Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92
P, T and RH Compensation Commands . . . . . . . . . . . . . . .92
Device Handling Commands . . . . . . . . . . . . . . . . . . . . . . . .92
Device Information Display Commands . . . . . . . . . . . . . . .92
Calibration Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93
Setting and Testing the Analog Outputs . . . . . . . . . . . . . . .93
Advanced Measurement Commands . . . . . . . . . . . . . . . . .93
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List of Figures
Figure 1 Two Models of GMP343. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Figure 2 Principle of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Figure 3 Components of the Sampling System . . . . . . . . . . . . . . . . . . .18
Figure 4 Examples of Optional Accessories. . . . . . . . . . . . . . . . . . . . . .18
Figure 5 Structure of the MI70 Indicator. . . . . . . . . . . . . . . . . . . . . . . . .20
Figure 6 Keyboard of MI70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Figure 7 Mounting GMP343. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Figure 8 Entering Measurement Values. . . . . . . . . . . . . . . . . . . . . . . . .42
Figure 9 The Difference of the Two Filters in Time Response. . . . . . . .44
Figure 10 Optics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71
Figure 11 GMP343 Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . .81
VAISALA________________________________________________________________________ 5
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List of Tables
Table 1 Manual Revisions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Table 2 Wiring Pins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Table 3 Communication Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Table 4 Quantities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Table 5 Modifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Table 6 Averaging Times . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Table 7 Troubleshooting Errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74
Table 8 Effect of Temperature on Accuracy with Temperature
Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78
Table 9 Effect of Pressure on Accuracy with Pressure Compensation. . .79
Table 10 Diffusion Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80
Table 11 Flow-through Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80
Table 12 List of Spare Parts and Accessories . . . . . . . . . . . . . . . . . . . . . .82
VAISALA________________________________________________________________________ 7
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Chapter 1 ________________________________________________________ General Information
CHAPTER 1
GENERAL INFORMATION
This chapter provides general notes for the manual and the product.
About This Manual
This manual provides information for installing, operating, and
maintaining the Vaisala CARBOCAP® Carbon Dioxide Probe
GMP343.
Version Information
Table 1 Manual Revisions
Manual Code Description
M210514EN-A October 2003 - First version.
M210514EN-B April 2005
M210514EN-C August 2007 - New probe housing
and software.
VAISALA________________________________________________________________________ 9
User's Guide ______________________________________________________________________
General Safety Considerations
Throughout the manual, important safety considerations are highlighted
as follows:
WARNING
CAUTION
NOTE
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 warns you of a potential hazard. If you do not read and follow
instructions carefully at this point, the product could be damaged or
important data could be lost.
Note highlights important information on using the product.
Feedback
Vaisala Customer Documentation Team welcomes your comments and
suggestions on the quality and usefulness of this publication. If you find
errors or have other suggestions for improvement, please indicate the
chapter, section, and page number. You can send comments to us by email: manuals@vaisala.com.
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.To
make sure you are not delivering high static voltages yourself handle
ESD sensitive components on a properly grounded and protected ESD
workbench. When this is not possible, ground yourself to the equipment
chassis before touching the connections. Ground yourself with a wrist
strap and a resistive connection cord. When neither of the above is
possible, touch a conductive part of the equipment chassis with your
other hand before touching the boards.
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Chapter 1 ________________________________________________________ General Information
Warranty
Vaisala hereby represents and warrants all Products
manufactured by Vaisala and sold hereunder to be free
from defects in workmanship or material during a
period of twelve (12) months from the date of delivery
save for products for which a special warranty is given.
If any Product proves however to be defective in
workmanship or material within the period herein
provided Vaisala undertakes to the exclusion of any
other remedy to repair or at its own option replace the
defective Product or part thereof free of charge and
otherwise on the same conditions as for the original
Product or part without extension to original warranty
time. Defective parts replaced in accordance with this
clause shall be placed at the disposal of Vaisala.
Vaisala also warrants the quality of all repair and
service works performed by its employees to products
sold by it. In case the repair or service works should
appear inadequate or faulty and should this cause
malfunction or nonfunction of the product to which the
service was performed Vaisala shall at its free option
either repair or have repaired or replace the product in
question. The working hours used by employees of
Vaisala for such repair or replacement shall be free of
charge to the client. This service warranty shall be
valid for a period of six (6) months from the date the
service measures were completed.
This warranty does not however apply when the defect
has been caused through
a) normal wear and tear or accident;
b) misuse or other unsuitable or unauthorized use of
the Product or negligence or error in storing,
maintaining or in handling the Product or any
equipment thereof;
c) wrong installation or assembly or failure to se rv ice
the Product or otherwise follow Vaisala's service
instructions including any repairs or installation or
assembly or service made by unauthorized personnel
not approved by Vaisala or replacements with parts not
manufactured or supplied by Vaisala;
d) modifications or changes of the Product as well as
any adding to it without Vaisala's prior authorization;
e) other factors depending on the Customer or a third
party.
Notwithstanding the aforesaid Vaisala's liability under
this clause shall not apply to any defects arising out of
materials, designs or instructions provided by the
Customer.
This warranty is however subject to following
conditions:
a) A substantiated written claim as to any alleged
defects shall have been received by Vaisala within
thirty (30) days after the defect or fault became known
or occurred, and
b) The allegedly defective Product or part shall, should
Vaisala so require, be sent to the works of Vaisala or to
such other place as Vaisala may indicate in writing,
freight and insurance prepaid and properly packed and
labelled, unless Vaisala agrees to inspect and repair the
Product or replace it on site.
This warranty is expressly in lieu of and excludes all
other conditions, warranties and liabilities, express or
implied, whether under law, statute or otherwise,
including without limitation any implied warranties of
merchantability or fitness for a particular purpose and
all other obligations and liabilities of Vaisala or its
representatives with respect to any defect or deficiency
applicable to or resulting directly or indirectly from the
Products supplied hereunder, which obligations and
liabilities are hereby expressly cancelled and waived.
Vaisala's liability shall under no circumstances exceed
the invoice price of any Product for which a warranty
claim is made, nor shall Vaisala in any circumstances
be liable for lost profits or other consequential loss
whether direct or indirect or for special damages.
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12 __________________________________________________________________ M210514EN-C
Chapter 2 __________________________________________________________ Product Overview
CHAPTER 2
PRODUCT OVERVIEW
This chapter introduces the features of the GMP343.
Introduction to GMP343
Vaisala CARBOCAP® Carbon Dioxide Probe GMP343 is designed for
high accuracy CO2 measurements. The measurement is based on the
advanced CARBOCAP® Single-Beam Dual-Wavelength NDIR
technology. GMP343 consists of a CO2 sensor, electronics, and a
housing suitable for long-term outdoor use.There are two GMP343
models available: a flow-through model and a diffusion model. One
adjustable analog output can be configured to output voltage or current
signal (0 ... 2.5 V, 0 ... 5 V, 4 ... 20 mA). A digital output for RS232/
RS485 communication is available. The measuring range options vary
from 0 ... 1000 ppm to 0 ... 2 %CO2.
The GMP343 can be ordered with various adapter, filter, and
connection cable options. For a list of spare parts and accessories, see
section Spare Parts and Accessories on page 82.
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User's Guide ______________________________________________________________________
GMP343 Transmitter Components
NOTE
Figure 1 Two Models of GMP343
The following numbers refer to Figure 1 above.
1=Filter
2 = Wiring connector
3=Gas in
4 = Gas out
5 = Back flange (do not open)
Warranty is void if the back flange of the GMP343 has been opened
by the user.
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Chapter 2 __________________________________________________________ Product Overview
User Configurable CO2 Measurement
The measurement output of the GMP343 is user configurable. You may
have the raw data without filtering or compensation, or you may set the
filtering levels, enable compensation (pressure, temperature, relative
humidity, and oxygen) and linearization.
You can also select the measurement range to optimize the performance
of the GMP343 for a certain concentration level. Selecting an
appropriate measurement range increases accuracy, since it enables the
range-specific compensation and linearization settings. For more
information, see sections Setting the Measurement Range on page 41
and Temperature, Pressure, Relative Humidity, and Oxygen
Compensations on page 47.
Principle of Operation
The infra-red sensor of GMP343 is based on the proprietary Vaisala
CARBOCAP® sensing technology. Here the pulsed light from a
miniature filament lamp is reflected and re-focused back to an IR
detector which is behind a silicon-based Fabry-Perot Interferometer
(FPI). This tiny FPI is tuned electrically so that its measurement
wavelength is changed between the absorption band of the CO2 gas and
a reference band.
Figure 2 Principle of Operation
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When the passband of the FPI coincides with the absorption wavelength
of the CO2 gas, the IR detector sees a decrease in the light transmission.
The measurement wavelength of the FPI is then changed to the
reference band (that has no absorption lines) and the IR detector sees a
full light transmission. The ratio of these two signals indicates the
degree of light absorption in the gas and is proportional to the gas
concentration. It takes 2 seconds to measure this sequence and to
calculate one reading.
Use of numerical filtering reduces the noise of the raw data. On the
other hand, the filtering increases the response time of the device (see
Figure 9 on page 44).
Optics Heating
Two heating elements are placed in the optics; one behind the mirror
and one behind the window of the sensor. Heating should always be
turned on when there is a risk of dew formation on the optics surface.
The heating maintains the surface temperature of the optics a few
degrees above the ambient temperature.
The heating is disabled by default. For instructions on how to control
the optics heating, refer to section Setting the Optics Heating ON/OFF
on page 61.
NOTE
The optics heating is automatically disabled when you connect the
GMP343 to a MI70 indicator.
Gas Sampling
There are two GMP343 models available: a flow-through model and a
diffusion model.
Diffusion Sampling
No sampling system is needed with the GMP343 diffusion model. The
diffusion filter and the plastic filter cover protect the measuring
chamber from dirt, water, and contaminants.
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In order to have a quick measurement with very short response time the
filter can be removed; see section Response time (90 %) on page 80. In
this case the optics are openly exposed to contamination and cleaning
of optics may be necessary more often. For instructions on cleaning the
optics, refer to section Cleaning the Optics (Diffusion Model Only) on
page 71. Removal of the filter is not recommended if there is a risk of
getting water or dirt particles on the optics.
Flow-Through Sampling
The maximum gas flow rate is 10 liters/min. When using high flow
rates, please note how the flow rate affects the accuracy, see
Specifications, Oxygen, on page 79 (flow dependence). The volume of
the internal measurement chamber is 59 ml ± 1 ml.
The gas sample must not include acidic gases.
CAUTION
Liquids or acidic vapors may seriously damage the sensor.
Sampling System
The GMP343 flow-through model has no diffusion filter inside the
measuring chamber and the optics of the flow-through model cannot be
cleaned by the user. Therefore the sample gas must always be filtered
and dried before it is pumped to the measuring chamber. A hydrophobic
diffusion filter before the inlet of the measuring chamber is needed in
order to prevent particles and water from the surroundings from getting
into the sensor. The diffusion filter needs to be exchanged often enough
to provide a sufficient flow.
In humid environments it is important to avoid water condensation
inside the measuring chamber. This can be avoided by drying the
sample air. The most common method of drying the sample air is
cooling and re-heating the air. A simple system may consist for example
of a cooling coil and a water trap which are either cooled or located in
a cool environment, followed by a re-heating system. The idea is to get
the moisture in the sample to condensate on the walls of the copper tube,
trap this water and then lower the relative humidity by heating the
sample. If the temperature inside the measurement chamber is
essentially higher than the surroundings the cooling coil and the water
trap can be simply located outside the chamber. For re-heating, the heat
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generated by a pumping system may sometimes be adequate, meaning
that no additional heater is needed. A simplified schema of a sample
system removing particles and moisture is illustrated below.
All sampling system components are commercially available.
Figure 3 Components of the Sampling System
Optional Accessories
Various adapter and filter options are available for the GMP343. For a
complete list, see section Spare Parts and Accessories on page 82.
Figure 4 Examples of Optional Accessories
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Chapter 2 __________________________________________________________ Product Overview
Soil Adapter Kits for In-Soil
Applications
The vertical/horizontal soil adapter kit consists of a soil adapter and a
hydrophobic sintered PTFE filter. The kits are designed for in-soil CO2
measurements to be used with the diffusion model of GMP343.
MI70 Indicator Connection
Vaisala MI70 indicator is an optional accessory to be used as a display,
communication, and data-logging device for GMP343. When taking
measurements GMP343 is powered via MI70.
Recharging the Battery Pack
MI70 indicator is equipped with a rechargable battery pack when
shipped from factory. The battery pack is located behind the back plate
of the indicator. The recharger is provided with one of the following
AC-adapters: Euro, UK, US or AUS.
1. Recharge the battery pack as follows: Plug in the recharger
connector into the connector on top of the indicator and connect the
recharger to a wall socket. A battery symbol in the corner of the
display starts to roll.
- It is not recommended to use MI70 during the first recharging.
Later on MI70 can be used while recharging.
- Duration of recharging depends on the charge level of the
battery pack being 4 hours typical. The recommended first
recharging time is 6 hours.
2. The battery pack is full when the battery symbol in the display
stops rolling.
3. Disconnect the recharger.
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Structure of the MI70 Indicator
Figure 5 Structure of the MI70 Indicator
The following numbers refer to Figure 4 above:
1 = Recharging connector
2 = Power On/Off key
3 = Connection cable (DRW216050SP) for GMP343 connection
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Using MI70 as a Display
Introduction of Function Keys and Menu Structure
NOTE
0704-034
Figure 6 Keyboard of MI70
The following numbers refer to Keyboard of MI70 on page 21:
1 = Function keys left/middle/right (can be assigned to shortcuts)
2 = Arrow keys up/down/left/right
3 = Power on/off key
Initialization of MI70
The optics heating is automatically disabled when you connect the
GMP343 to the MI70 indicator.
1. Install the connection cable between MI70 and GMP343 (GMP343
is powered from MI70).
2. Turn on MI70 by pressing the Power On/Off key.
3. Select the language by using the up/down arrow keys. Confirm by
pressing the SELECT key.
4. To change the date, select Date and press the SET key. Set the date
by using the up/down/left/right arrow keys. To confirm the date,
press the OK key.
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5. To change the time, select Time and press the SET key. Set the
time by using the up/down/left/right arrow keys. To confirm the
time, press the OK key.
6. To check and change the environment settings, select YES. Enter
ambient pressure, humidity, and oxygen values. Press the EXIT
key.
Navigation in Menu
- To turn the indicator on or off, press the Power On/Off key.
- To open the main menu, press any of the arrow keys and then the
middlemost function key in sequence.
- To move in a menu and select an option, press the up/down arrow
keys. To enter sub-menu of selected option, press the right arrow
key. To return to the previous menu level, press the left arrow key.
- To activate a function: press a function key according to the
guiding text below the key.
- To return to the basic display directly from any menu levels, press
the function key EXIT.
The main settings are found in the following menu locations:
- To change language, enter: Settings - User interface - Language.
- To select display quantities (carbon dioxide and temperature),
enter: Display - Quantities and units. The carbon dioxide
concentration is shown in ppm or in %-units and temperature in
°C or °F.
- To set the ambient conditions enter Environment menu. Options
to choose from: 1013 hPa, 50 % RH, and 20.9 % O2.
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Using MI70 in Recording
Record continuous measurement data and view the recorded data by
using the MI70. This function is found from the menu RECORDING/
VIEWING.
You can switch MI70 off during recording to save battery power.
Display message tells you that recording continues undisturbed even
when the power is off. If the indicator is switched off during recording,
the progress bar is shown on the display every 10 seconds (all the time,
if the charger is connected). This bar shows the amount of recorded
data.
Save individual measurement data points with Hold/Save function
(DISPLAY-HOLD/SAVE DISPLAY) and view the saved data from
the RECORDING/VIEWING menu.
CAUTION
Do not disconnect the probe when the data recording is on, even if the
indicator is off. This may cause loss of recorded data.
Transferring Recorded Data to PC
The recorded data can be transferred to a PC by using MI70 Link
program. MI70 Link program can be ordered from Vaisala, see Table
12, List of Spare Parts and Accessories, on page 82. You can examine
the recorded data easily in Windows and transfer it further to a
®
spreadsheet program (such as Microsoft
More information on the data transfer and software features is found in
the HELP-file of MI70 Link program.
Excel) for modification.
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Chapter 3 _______________________________________________________________ Installation
CHAPTER 3
INSTALLATION
This chapter provides you with information that is intended to help you
install this product.
Mounting
A horizontal mounting position is recommended in order to minimize
the problems caused by possible condensation.
0704-020
Figure 7 Mounting GMP343
1. Fasten the GMP343 to the mounting bracket by using the screw
provided.
2. Mount the mounting bracket with 4 screws (on corners of the
plate).
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Wiring
As it is shipped from the factory, the measurement range and output of
the GMP343 are scaled according to the order form completed by the
customer. The unit is calibrated at the factory. The device is ready for
use when the wiring is done and power is switched on.
GMP343 can be connected to a PC using an optional PC connection
cable, see Table 12, List of Spare Parts and Accessories, on page 82.
For more information on serial commands, see Chapter 4, Operation, on
page 29.
WARNING
Make sure that the main power is switched off before making any
electrical connections.
Table 2 Wiring Pins
Pin Wire Serial signal (RS232 or 2-
Wire RS485 interface)
1 White RS232C: TX RS485: A(+) 2 Brown RS232C: TX RS485: A(+) 3 Green RS232C: RX RS485: B(-) 4 Yellow - - Signal +
5 Grey Supply GND Supply GND Supply GND
6 Pink +11...36 V DC +11...36 V DC +11...3 6 V DC
7 Blue RS232C: RX RS485: B(-) 8 Shield - - Signal GND
Analog signal
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Chapter 3 _______________________________________________________________ Installation
There are two pins per signal internally hardwired in parallel (pins 1 and
2, pins 3 and 7). You should connect the RS232C signal 'TX' (or 2-Wire
RS485 signal 'A') either to the pin 1 or 2 and the RS232C signal 'RX' (or
2-Wire RS485 signal 'B') either to the pin 3 or 7.
Note that there is either an RS232 or a 2-wire RS485 communication
interface available according to initial configuration. However, if the
device is configured in RS485 output mode, the device can still be
switched into RS232 mode by re-configuration via PC . For more
information on serial commands and RS232/485 modes, see Chapter 4,
Operation, on page 29.
Wiring of the Junction Box
The optional 8-pole junction box enables practical in-line connection.
The box is provided with 8 numbered terminals.
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