Vaisala GMP231 User Manual
USER'S GUIDE
Vaisala CARBOCAP® Carbon Dioxide Probe
GMP231
M211501EN-C
PUBLISHED BY
Vaisala Oyj
Street address: Vanha Nurmijärventie 21, FI-01670 Vantaa, Finland
Mailing address: P.O. Box 26, FI-00421 Helsinki, Finland
Phone: +358 9 8949 1
Fax: +358 9 8949 2227
Visit our Internet pages at www.vaisala.com.
© Vaisala 2014
No part of this manual may be reproduced, published or publicly displayed in any form
or by any means, electronic or mechanical (including photocopying), nor may its
contents be modified, translated, adapted, sold or disclosed to a third party without prior
written permission of the copyright holder. Translated manuals and translated portions
of multilingual documents are based on the original English versions. In ambiguous
cases, the English versions are applicable, not the translations.
The contents of this manual are subject to change without prior notice.
This manual does not create any legally binding obligations for Vaisala towards
customers or end users. All legally binding obligations and agreements are included
exclusively in the applicable supply contract or the General Conditions of Sale and
General Conditions of Service of Vaisala.
_________________________________________________________________________________
Table of Contents
CHAPTER 1
GENERAL INFORMATION ............................................................................ 7
About This Manual ................................................................... 7
Contents of This Manual ....................................................... 7
Version Information ............................................................... 8
Related Manuals ................................................................... 8
Documentation Conventions ................................................. 8
Safety ......................................................................................... 9
ESD Protection ...................................................................... 9
Recycling .................................................................................. 9
Regulatory Compliances ....................................................... 10
Patent Notice .......................................................................... 10
Trademarks ............................................................................. 10
Software License .................................................................... 10
Warranty .................................................................................. 11
CHAPTER 2
PRODUCT OVERVIEW ................................................................................ 12
Introduction to GMP231 ......................................................... 12
Basic Features and Options .................................................. 13
GMP231 Parts ......................................................................... 14
Operating Principle of CO2 Measurement ............................ 15
Environmental Compensation .............................................. 17
Pressure Compensation ...................................................... 17
Temperature Compensation ............................................... 17
Background Gas Compensations ....................................... 18
Probe Startup .......................................................................... 18
Analog Output Overrange Behavior ..................................... 19
CHAPTER 3
INSTALLATION ............................................................................................ 20
Thermal Management ............................................................ 20
Avoiding Condensation ......................................................... 21
Probe Installation Depth ........................................................ 21
Dimensions ............................................................................. 22
Recommended Installation ................................................... 23
Wiring ...................................................................................... 24
Power Supply .......................................................................... 24
CHAPTER 4
VAISALA INDUSTRIAL PROTOCOL .......................................................... 25
Overview ................................................................................. 25
VAISALA _________________________________________________________________________ 1
User's Guide _______________________________________________________________________
Physical Interface ................................................................... 25
Connecting with a Computer ................................................. 26
Installing the Driver for the USB Service Cable ............. 26
Terminal Application Settings ......................................... 27
Serial Commands ................................................................... 28
Showing Device Information ................................................. 29
Show Probe Information ...................................................... 29
Show Serial Number ............................................................ 30
Show Firmware Version ...................................................... 30
Show Firmware Information ................................................ 30
Show Probe Uptime ............................................................. 30
Show Command List ........................................................... 31
Serial Line Output Commands .............................................. 31
Start Measurement Output .................................................. 31
Stop Measurement Output .................................................. 32
Set Output Interval ............................................................... 32
Output a Reading Once ....................................................... 32
Set Measurement Output Format ........................................ 33
FORM Command Examples .......................................... 34
Changing Measurement Settings .......................................... 35
Set Compensation Modes ................................................... 35
Change Compensation Setpoint Values ............................. 36
Set Measurement to Standby Mode .................................... 37
Configuring Serial Line Operatio n ........................................ 38
Set Serial Line Operating Mode .......................................... 38
Set Serial Line Settings ....................................................... 39
Set Probe Address .............................................................. 39
Set Serial Line Response Time ........................................... 40
Set Serial Line Echo ....................................................... 40
Calibration Commands .......................................................... 41
Adjust CO2 Measurement .................................................... 41
Set Calibration Date ............................................................ 42
Set Calibration Info Text ...................................................... 43
Adjust Temperature Measurement ...................................... 43
Adjust Pressure Measurement ............................................ 44
Configuring Analog Output ................................................... 45
Set Analog Output Scaling .................................................. 45
Set Analog Output Mode ..................................................... 45
Set Analog Output Clipping and Error Limit ........................ 46
Test Analog Output .............................................................. 47
Other Commands.................................................................... 47
Enable Advanced Commands ............................................. 47
Connecting to Probe in POLL Mode .................................... 48
Closing the Connection to a Probe in POLL Mode ............. 48
Show Active Errors .............................................................. 48
Reset Probe ......................................................................... 49
Restore Factory Settings ..................................................... 49
CHAPTER 5
I2C INTERFACE ............................................................................................ 50
Overview .................................................................................. 50
Physical Interface ................................................................ 50
Communication Param eters ................................................ 51
Addressing ........................................................................... 51
2 ____________________________________________________________________ M211501EN-C
_________________________________________________________________________________
Communication Flow ............................................................. 52
GMP231 State Machine ...................................................... 53
Examples of Communication Flow ...................................... 54
Timing .................................................................................. 56
Status Byte .......................................................................... 56
Checksum ........................................................................... 56
Status Word......................................................................... 57
Commands .............................................................................. 58
Get_Interface_Version ........................................................ 58
Get_Parameter .................................................................... 59
Example: Read CO2 Measurement Result .................... 60
Set_Parameter .................................................................... 61
Example: Set Compensation Temperature ......................... 62
Get_Parameter_Info ............................................................ 63
Adjust .................................................................................. 64
Adjusting Measurement......................................................... 65
One Point Adjustment ......................................................... 65
Two Point Adjustment ......................................................... 66
Data Registers ........................................................................ 66
Data Formats....................................................................... 66
Register Table ..................................................................... 67
CHAPTER 6
MAINTENANCE ........................................................................................... 70
Cleaning .................................................................................. 70
Chemical Tolerance ............................................................ 70
Changing the Filter ................................................................. 71
Changing the Silicone Plug ................................................... 72
Calibration and Adjustment .................................................. 73
Calibration Setup ................................................................. 73
Using Ambient Air as Reference .................................... 74
Using a Calibration Gas as Reference........................... 74
Effect of Environmental Compensations ............................. 74
Limits of Adjustment ............................................................ 75
Adjustment Types ............................................................... 75
I2C Interface ................................................................... 76
Vaisala Industrial Protocol ............................................. 76
MI70 Hand-Held Indicator .............................................. 76
CHAPTER 7
OPERATING WITH MI70 INDICATOR ........................................................ 77
Overview of MI70 Support ..................................................... 77
Connecting GMP231 to MI70 Indicator ................................. 77
Changing Environmental Compensation Settings with MI70
Indicator .................................................................................. 78
Calibration and Adjustment with MI70 Indicator ................. 79
1-Point Adjustment with an MI70-Compatible Reference
Probe ................................................................................... 79
1-Point Adjustment with a Reference Gas .......................... 81
CHAPTER 8
TROUBLESHOOTING ................................................................................. 83
Problem Situations ................................................................. 83
VAISALA _________________________________________________________________________ 3
User's Guide _______________________________________________________________________
Analog Output Error State ..................................................... 84
Technical Support .................................................................. 84
Product Returns...................................................................... 84
CHAPTER 9
TECHNICAL DATA ...................................................................................... 85
Specifications ......................................................................... 85
Spare Parts and Accessories ................................................ 87
4 ____________________________________________________________________ M211501EN-C
_________________________________________________________________________________
List of Figures
Figure 1 GMP231 Installed Through a Chamber Wall (Example) .......... 12
Figure 2 GMP231 Parts .......................................................................... 14
Figure 3 CARBOCAP® Sensor of the GMP231 ...................................... 15
Figure 4 CO2 Measurement Inside the Incubator ................................... 16
Figure 5 Probe Installation Depth ........................................................... 21
Figure 6 Probe Dimensions without Silico ne Plu g .................................. 22
Figure 7 Probe Dimensions with Silicone Plug ....................................... 22
Figure 8 Electronics Housing Dimensions .............................................. 22
Figure 9 Attachment Bracket Dimensions .............................................. 22
Figure 10 Recommended Installation ....................................................... 23
Figure 11 PuTTY Terminal Application..................................................... 27
Figure 12 Hardware Schematic ................................................................ 50
Figure 13 GMP231 State Machine ........................................................... 54
Figure 14 Get_Parameter with ACK ......................................................... 54
Figure 15 Set_Parameter with ACK ......................................................... 55
Figure 16 Get_Parameter with NACK ...................................................... 55
Figure 17 Get_Parameter with Alarm ....................................................... 55
Figure 18 Changing the Filter ................................................................... 71
Figure 19 Changing the Silicone Plug ...................................................... 72
Figure 20 Inserting the Calibration Adapter over the Filter ...................... 73
Figure 21 CO2 Reading on MI70 Screen .................................................. 77
Figure 22 CO2 Reading with Tcomp and Pcomp on MI70 Screen ........... 78
Figure 23 GMP231 Compensation Settings on MI70 Screen .................. 78
Figure 24 Functions Menu ........................................................................ 79
Figure 25 Comparing Readings in MI70 Adjustment Mode ..................... 80
Figure 26 Selecting the Adjustment Mode ............................................... 80
Figure 27 Functions Menu ........................................................................ 81
Figure 28 MI70 Adjustment Mode ............................................................ 81
Figure 29 Selecting the Adjustment Mode ............................................... 82
Figure 30 Entering the Reference CO2 Concentration ............................. 82
VAISALA _________________________________________________________________________ 5
User's Guide _______________________________________________________________________
List of Tables
Table 1 Manual Revisions ....................................................................... 8
Table 2 Related Manuals ......................................................................... 8
Table 3 Applicable Patents .................................................................... 10
Table 4 GMP231 Connector Pinout ....................................................... 24
Table 5 Cable DRW240977 ................................................................... 24
Table 6 Default Serial Interface Settings ............................................... 25
Table 7 Basic Serial Commands ........................................................... 28
Table 8 Advanced Serial Commands .................................................... 29
Table 9 FORM Command Parameters .................................................. 33
Table 10 FORM Command Modifiers ...................................................... 33
Table 11 Selection of Output Modes ....................................................... 38
Table 12 GMP231 I2C Address ............................................................... 51
Table 13 GMP231 Device Address ......................................................... 51
Table 14 Invoke Message in GMP231 I2C Interface ............................... 52
Table 15 Response Message in GMP231 I2C Interface .......................... 53
Table 16 Timing ....................................................................................... 56
Table 17 Status Byte ............................................................................... 56
Table 18 Status Word Content ................................................................ 57
Table 19 Get_Interface_Version Invoke Message .................................. 58
Table 20 Get_Interface_Version Response Message ............................. 58
Table 21 Get_Parameter Invoke Message .............................................. 59
Table 22 Get_Parameter Response Message ........................................ 59
Table 23 Get_Parameter Invoke Message Example ............................... 60
Table 24 Get_Parameter Response Mes s age Example ......................... 60
Table 25 Set_Parameter Invoke Message .............................................. 61
Table 26 Set_Parameter Response Message......................................... 61
Table 27 Set_Parameter Return Codes .................................................. 61
Table 28 Example Set_Parameter Invoke Message ............................... 62
Table 29 Example Set_Parameter Response Message ......................... 62
Table 30 Get_Parameter_Info Invoke Message ...................................... 63
Table 31 Get_Parameter_Info Response Message ................................ 63
Table 32 Parameter Data Types ............................................................. 63
Table 33 Parameter Persistence ............................................................. 63
Table 34 Adjust Invoke Message ............................................................ 64
Table 35 Adjust Response Message ....................................................... 64
Table 36 Adjustment Subcommands ....................................................... 64
Table 37 Adjustment Parameters ............................................................ 64
Table 38 Adjustment Return Codes ........................................................ 65
Table 39 Data Formats ............................................................................ 66
Table 40 GMP231 Register Table ........................................................... 67
Table 41 Possible Problem Situations and Their Remedies ................... 83
Table 42 Performance ............................................................................. 85
Table 43 Operating Environm ent ............................................................. 86
Table 44 Inputs and Outputs ................................................................... 86
Table 45 Mechanics ................................................................................. 86
Table 46 Spare Parts and Accessories for GMP231 ............................... 87
6 ____________________________________________________________________ M211501EN-C
Chapter 1 _________________________________________________________ General Information
CHAPTER 1
GENERAL INFORM ATION
This chapter provides general notes for the manual and the GMP231
probe.
About This Manual
This manual provides information for installing, operating, and
maintaining the Vaisala CARBOCAP® Carbon Dioxide Probe GMP231.
Contents of This Manual
This manual consists of the following chapters:
- Chapter 1, General Informati on, provides general notes for the manual
and the GMP231 probe.
- Chapter 2, Product Overview, introduces the GMP231 probe and its
features.
- Chapter 3, Installation, provides you with information that is intended
to help you install the GMP231.
- Chapter 4, Vaisala Industrial Protocol, describes the Vaisala Industrial
Protocol implementation of the GMP231.
- Chapter 5, I2C Interface, describes the I2C interface implementation
of the GMP231.
- Chapter 6, Maintenance, provides information that is needed in the
basic maintenance of the GMP231.
- Chapter 8, Troubleshooting, describes possible problems, their
probable causes and remedies, and provides contact information for
technical support.
- Chapter 9, Technical Data, provides the technical data of the
GMP231.
VAISALA _________________________________________________________________________ 7
User's Guide _______________________________________________________________________
Manual Code
Description
M211501EN-C
May 2014. This manual. Updated description for
Setpoint Values on page 36.
M211501EN-B
Previous version. Applicable from software version
and adjustment. Updated technical specification.
M211501EN-A
September 2013. First version.
Manual Code
Manual Name
M211603EN
GMP231 Quick Guide
Version Information
Table 1 Manual Revisions
ENV command in section Change Compensation
1.1.0 onward. Added instructions for operation with
the MI70 hand-held indicator. Updated description
2
C interface and Vaisala Industrial Prot oc ol.
of I
Updated description of envir onmental
compensations. Updated instructions for calibration
Related Manuals
Table 2 Related Manuals
WARNING
CAUTION
NOTE
Documentation Conventions
Throughout the manual, important safety considerations are highlighted
as follows:
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.
8 ____________________________________________________________________ M211501EN-C
Chapter 1 _________________________________________________________ General Information
When returning a product for calibration or repair, make sure it has not
been exposed to dangerous contamination, and is safe to handle without
special precautions.
Do not modify the unit. Improper modification can damage the
or lead to malfunction.
Do not open the
inside.
Recycle all applicable material.
Dispose of the unit according to statutory regulations. Do not dispose of
with regular household refuse.
Safety
The GMP231 probe delivered to you has been tested for safety and
approved as shipped from the factory. Note the following precautions:
WARNING
CAUTION
CAUTION
Recycling
product
probe housing. There are no user serviceable parts
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. It is possible to damage the product,
however, by delivering an electrostatic discharge when touching an
exposed contact on the product.
To make sure you are not delivering high static voltages yourself, avoid
touching the pins on the M12 connector.
VAISALA _________________________________________________________________________ 9
User's Guide _______________________________________________________________________
Patent Issued By
Patent Number
United States Patent and Trademark Office
US 5,827,438
US 6,177,673
European Patent Office
EP0776023
EP0922972
German Patent and Trade Mark Office
69615635
Japan Patent Office
4263285
Finnish Patent Office
112005
105598
Regulatory Compliances
GMP231 is in conformity with the provisions of the following
EU directives:
- EMC-Directive
- RoHS-Directive
Conformity is shown by compliance with the following standards:
- EN 61326-1: Electrical equipment for measurement, control, and
laboratory use – EMC requirements – Generic environment.
- EN 550022: Information technology equipment – Radio disturbance
characteristics – Limits and methods of measurement.
Patent Notic e
GMP231 is protected by the following patents and their corresponding
national rights:
Table 3 Applicable Patents
Trademarks
CARBOCAP® is a registered trademark of Vaisala Oyj.
All other trademarks are the property of their respective owners.
Software License
This product contains software developed by Vaisala. Use of the software
is governed by license terms and conditions included in the applicable
supply contract or, in the absence of separate license terms and
conditions, by the General License Conditions of Vaisala Group.
10 ___________________________________________________________________ M211501EN-C
Chapter 1 _________________________________________________________ General Information
Warranty
Visit our Internet pages for standard warranty terms and conditions:
www.vaisala.com/warranty.
Please observe that any such warranty may not be valid in case of
damage due to normal wear and tear, exceptional operating conditions,
negligent handling or installation, or unauthorized modifications. Please
see the applicable supply contract or Conditions of Sale for details of the
warranty for each product.
VAISALA ________________________________________________________________________ 11
User's Guide _______________________________________________________________________
CHAPTER 2
PRODUCT OVERVIE W
This chapter introduces the GMP231 probe and its features.
Introduction to GMP231
The Vaisala CARBOCAP® Carbon Dioxide Probe GMP231 is designed
for incubator manufacturers requiring accurate and reliable carbon
dioxide measurements and sterilization durability at high temperatures.
The GMP231 probe is based on Vaisala’s patented CARBOCAP®
technology and a new type of infra-red light source. The probe can
remain in place during high-temperature sterilization cycles that heat the
chamber interior to 180 °C. Special design of the probe enables easy
installation through the incubator wall and ensures that the sensor optics
and electronics are separated and thermally insulated.
Sensor performance is optimized at 5 %CO2 measurement. GMP231 also
has an internal pressure sensor, which allows compensation of the
measurement according to ambient pressure. Since dust and most
chemicals do not affect the measurement, and the effect of water vapor
can be compensated for, GMP231 is accurate and stable at CO2 incubator
conditions.
1403-144
Figure 1 GMP231 Installed Through a Chamber Wall (Example)
12 ___________________________________________________________________ M211501EN-C
Chapter 2 ___________________________________________________________ Product Overview
Basic Features and Options
- CO2 measurement range 0 ... 20 %CO2.
- Temperature durability in standby mode up to 195 °C (383 °F). See
section Thermal Management on page 20.
- Vaisala CARBOCAP® CO2 sensor with excellent long-term stability.
See sections Operating Principle of CO2 Measurement on page 15 and
Specifications on page 85.
- Measurement compensated for effects of pressure, temperature, and
background gas. Pressure compensation based on integrated pressure
sensor. See section Environmental Compensation on page 17.
- Heating to avoid condensation on optical elements.
- Analog output: one current output channel (0 ... 20 mA or 4 ... 20 mA).
- Digital output:
- I2C.
- RS-485 (non-isolated) with Vaisala Industrial Protocol.
VAISALA ________________________________________________________________________ 13
User's Guide _______________________________________________________________________
1 = Electronics housing. Contains the main component board,
including the digital pressure sensor.
2 = Holes for M4 screws on both sides of the housing.
Maximum
BN 10649 M4.
3 = Type label on housing cover (not shown).
4 = 8-pin M12 connector. For pinout, see Table 4 on page 24.
5 = Probe body.
6 = Measurement cuvette with optics and CARBOCAP® CO2 sensor.
7 = PTFE filter.
8 = Silicone plug for sealing the lead-through.
Recommended accessory, suitable for ⌀ 44 mm lead-throughs.
3
2
4
1
5
6
7
8
GMP231 Parts
CAUTION
1403-153
Figure 2 GMP231 Parts
screw depth 8 mm. Two screws included, type
Do not open the electronics housing; there are no user serviceable parts
inside. All wiring is done through the M12 connector (4).
14 ___________________________________________________________________ M211501EN-C
Chapter 2 ___________________________________________________________ Product Overview
1 = Cuvette.
2 = Mirror.
3 = Window.
4 = Sensor chips.
2
3
4
1
Operating Principle of CO2 Measurement
The Vaisala CARBOCAP® sensor that is used in the GMP231 is a siliconbased, non-dispersive infrared (NDIR) sensor for the measurement of
gaseous carbon dioxide. It is especially designed to tolerate high
temperatures in standby mode, up to 195 °C (383 °F). This allows it to be
used in applications that utilize high temperature for heat sterilization. The
operating temperature range of the sensor is 0 … +70 °C (+32 ... +158 °F).
1403-160
Figure 3 CARBOCAP® Sensor of the GMP231
The sensitivity to carbon dioxide is based on absorption of infrared light
at a characteristic wavelength. The light is emitted by a novel, siliconbased microchip emitter into the cuvette which contains the gas to be
measured. After reflection from the mirror, the light intensity is measured
with a thermopile chip at a wavelength chosen by a micromechanical
Fabry–Pérot interferometer (FPI) and a band pass filter. A hermetically
sealed sapphire window is used to protect the sensor chips from moisture
and contamination. A heater chip is utilized to prevent condensation in
normal operation.
The carbon dioxide measurement consists of two steps: First, the FPI is
electrically tuned so that its pass band coincides with the characteristic
absorption wavelength of carbon dioxide and the signal is recorded.
Second, the pass band is shifted to a wavelength where no absorption
occurs in order to get a reference signal. The ratio of these two signals,
one at the absorption wavelength and the other at the reference
wavelength, gives the fraction of light absorption from which the carbon
dioxide concentration is calculated. The reference signal compensates the
possible effects of sensor aging and signal attenuation due to dirt on
optical surfaces, making the sensor very stable over time.
VAISALA ________________________________________________________________________ 15
User's Guide _______________________________________________________________________
1 = Chamber wall.
2 = Chamber interior.
3 = Light source.
4 = Band pass filter.
5 = Ambient air (400 ... 1000 ppm CO2).
6 = Light absorbed by CO2 in the incubator gas.
7 = Thermopile detector.
8 = Fabry-Perot interferometer.
9 = Sapphire window. Separates the sensor’s active components
from the measured environment.
10 = Gold-plated mirror.
1
2
3 4
5
6
7
8
9 10
1403-161
Figure 4 CO2 Measurement Inside the Incubator
16 ___________________________________________________________________ M211501EN-C
Chapter 2 ___________________________________________________________ Product Overview
Environmental Compensation
GMP231 improves the CO2 measurement accuracy by applying various
environmental compensations. GMP231 compensates for the effects of:
- Pressure
- Temperature
- Background gas oxygen (O2) content
- Background gas relative humidity (%RH)
Compensation parameters are configured on the order form when
ordering the probe, and can later be updated using serial commands,
MI70 Indicator, or I2C protocol. If the probe is integrated in a system that
measures one or more of the compensation parameters, they can be
updated to the probe continuously.
You can also turn off any of the compensations. In that case, GMP231
uses the default compensation value that is mathematically neutral for the
probe’s internal compensation model.
For the effect of the compensations on measurement accuracy, refer to
Table 42 on page 85.
Pressure Compensation
There is a pressure sensor on the component board of the GMP231 that
provides a live measurement of ambient pressure. GMP231 can
compensate the CO2 measurement based on this pressure reading, or it
can use a fixed setpoint. Using the GMP231’s own sensor is
recommended for most applications.
If pressure compensation is turned off, GMP231 uses the default
compensation value of 1013.2 hPa.
Temperature Compensation
GMP231 can measure the approximate temperature of the CARBOCAP®
sensor for compensation, or use a fixed setpoint. The temperature
measurement is accurate enough to be useful for compensation, and is
recommended for use unless a dedicated temperature measurement is
available and can be regularly updated to the GMP231.
If temperature compensation is turned off, GMP231 uses the default
value of +37 °C (+98.6 °F).
VAISALA ________________________________________________________________________ 17
User's Guide _______________________________________________________________________
Background Gas Com p e nsations
Compensation for background gas parameters are based on setpoint
values only, as GMP231 has no internal measurement for oxygen
concentration or humidity. The default setpoint values are as follows:
- Oxygen concentration: 19.7 %O2.
- Relative humidity: 93 %RH.
If background gas compensations are turned off, GMP231 uses the value
0% for both.
Probe Startup
When powered on, GMP231 starts up within 10 seconds. Measurements
from the outputs (digital and analog) become available during this time
but note that they will only reach specified accuracy after a one minute
warm-up period. For this reason, you should design the incubator’s
control system so that it does not rely on measurements from GMP231
during this time.
NOTE
Specifically note that the CO2 reading will rise to the correct reading as
the sensor’s infrared emitter achieves operation temperature.
18 ___________________________________________________________________ M211501EN-C
Chapter 2 ___________________________________________________________ Product Overview
This overrange and error state behavior is specific to the analog output,
and
Analog Output Overrange Behavior
Analog output of the GMP231 has a defined behavior when the values
measured by the probe are outside the scaled analog output range:
- Output is allowed to go 10% over the scaled range.
- Output is set to error state when measured value is more than 10%
outside the scaled range. See section Analog Output Error State on
page 84.
- Output resumes normal function when measured value returns to
within 10% of the selected range.
For example, consider a GMP231 with 0 ... 20 mA analog output, scaled
to 0 ... 10 %CO2.
- When measured CO2 rises above 10 %CO2, the output rises above
20 mA.
- The output keeps rising until the measurement is 11 %CO2, at which
point the probe outputs 22 mA.
NOTE
- If the CO2 level rises above 11 %CO2, the output enters the error
state, which is 23 mA for the 0 ... 20 mA output.
does not affect the readings provided by the digital outputs.
You can change the analog output overrange behavior using the AOVER
command. See section Set Analog Output Clipping and Error Limit on
page 46.
VAISALA ________________________________________________________________________ 19
User's Guide _______________________________________________________________________
CHAPTER 3
INSTALLATION
This chapter provides you with information that is intended to help you
install the GMP231.
Thermal Management
GMP231 is designed to remain installed during typical heat sterilization
cycles that raise the chamber temperature to 180 °C (356 °F). Since
180 °C is the target temperature for sterilization, it is likely that there will
be hotspots inside the chamber that are above this temperature. Avoid
installing the GMP231 near such hotspots, for example near heating
elements. Do not expose the GMP231 to temperatures higher than 195 °C
/ 383 °F.
The following considerations are most important for achieving the
specified heat durability and measurement stability:
- Only the sensor and its filter should be exposed to heat. The filter
must be completely in the heated chamber. The probe body must
remain inside the unheated chamber wall so that only the end of the
probe body extends exactly 2.5 mm into the chamber.
- During the sterilization cycle, you must set the GMP231 to
standby mode (turns off the CO2 measurement), or power off the
probe completely. The GMP231 will automatically stop its
measurement cycle if it detects a high temperature, but it is best if the
incubator’s control system set the GMP231 to standby mode when the
sterilization cycle is started.
- The installation tube must be sealed from the chamber side to limit
heat conduction, and to prevent CO2 in the chamber from entering the
probe. Vaisala recommends a 44 mm diameter installation tube
together with Vaisala’s silicone plug.
- If the chamber wall contains heating elements, or has a construction
where hot air is circulated inside the wall, design the installation tube
so that excessive heat is not conducted to the GMP231.
20 ___________________________________________________________________ M211501EN-C
Chapter 3 ________________________________________________________________ Installation
2.5 mm
Avoiding Condensation
The sensor head of the GMP231 is heated during normal operation,
which prevents condensation from forming inside the filter and on the
optical surfaces. The heating is not on when GMP231 is in standby mode
or unpowered. For this reason, keep the probe powered and operating
when the incubator is in use and humidity inside the chamber is high.
Correct installation depth of the probe is also important for preventing
condensation from running to the sensor along the chamber wall.
See below.
Probe Installation Depth
GMP231 must be installed so that only the sensor element and the filter
are inside the chamber. If the probe is longer the installation tube, the
extra length should extend to the outside of the chamber.
The installation depth must be 2.5 mm. This installation depth provides
the specified heat durability of the probe, and allows the silicone plug to
seal the Ø44 mm installation tube properly.
1403-154
Figure 5 Probe Installation Depth
VAISALA ________________________________________________________________________ 21
User's Guide _______________________________________________________________________
163
118.5
Screw BN 10649 M4 x 8 mm
(for 1 mm thick sheet metal
attachment)
1121
Ø 30.2
1.3°
Ø 19
Ø 24.8
Position only the filter
inside the heated chamber
163
118.5
Screw BN 10649 M4 x 8 mm
(for 1 mm thick sheet metal
attachment)
1121
Ø 30.2
Ø 19
2.5
Incubator’s inner wall
1.3°
Position only the filter
inside the heated chamber
Recommended diameter
for installation tube 44 mm
M12
54.4
87
Reserve space for M12 cable
40
4 × Ø3.5
52
Dimensions
1403-108
Figure 6 Probe Dimensions without Silicone Plug
1403-110
Figure 7 Probe Dimensions with Silicone Plug
1403-112
Figure 8 Electronics Housing Dimensions
22 ___________________________________________________________________ M211501EN-C
1403-109
Figure 9 Attachment Bracket Dimensions
Chapter 3 ________________________________________________________________ Installation
The probe and electronics housi
chamber. The electronics housing should be in a ventilated space that is
open to ambient air.
1 = Ambient air.
2 = Chamber wall.
3 = Chamber interior.
4 = GMP231 Electronics housing.
5 = M4 screw holes on both sides of the probe housing.
6 = 8-pin M12 connector. For pinout, see section Wiring on page 24.
7 = Cable.
8 = CARBOCAP® sensor under PTFE filter. The filter must be inside
the chamber completely.
9 = Silicone plug. Insert the plug over the probe from inside the
chamber.
10 = Ø 44 mm installation tube through the chamber wall.
The diameter is important for proper sealing by the silicone plug.
4
1
2
3
5
6
7
9
8
10
Recommended Installation
GMP231 is designed to be installed through a chamber wall, and attached
to the chamber chassis using an attachment bracket and the two screw
holes on the side of the probe. As the installation depth of the probe
inside the chamber is critical (see section Probe Installation Depth on
page 21), the mounting method must allow the probe to be positioned
exactly.
NOTE
ng must remain outside the heated
1403-123
Figure 10 Recommended Installation
VAISALA ________________________________________________________________________ 23
User's Guide _______________________________________________________________________
Male 8-pin M12
Pin #
Function
1
I2C SDA
2
RS-485 D-
3
I2C SCL
4
Analog output +
5
Standby
6
RS-485 D+
7
Power supply +
8
Ground
-
Shield
Female 8-pin M12
Pin #
Function
Wire Color
1
I2C SDA
White
2
RS-485 D-
Brown
3
I2C SCL
Green
4
Analog output +
Yellow
5
Standby
Gray
6
RS-485 D+
Pink
7
Power supply +
Blue
8
Ground
Red
-
Shield
Black
1
5
6
7
3
4
8
2
1
6
8
7
3
4
5
2
Wiring
GMP231 provides several outputs you can use. Connect the output pins
you need, and the power supply and ground pins. Use a shielded cable,
and connect the shield to the chassis of the GMP231’s M12 connector,
and to ground on the other side.
Ground pin 5 to put the probe in standby mode (stops CO2 measurement).
The probe resumes normal measurement operation when pin 5 is no
longer grounded, unless its internal measurement shows the temperature
is too high.
Table 4 GMP231 Connector Pinout
Vaisala’s standard connection cable for the GMP231 (order code
DRW240977) is a 90 cm long cable with female 8-pin M12 connector on
one end, and open ended wires on the other. It supports all outputs from
the GMP231, and connects the cable shield to the connector chassis.
Table 5 Cable DRW240977
Power Supply
24 ___________________________________________________________________ M211501EN-C
The supply voltage range of the GMP231 is 11 ... 30 VDC.
If the analog output is used, the supply voltage range is 20 ... 30 VDC.
The maximum power consumption is 1 W.
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol
Property
Description / Value
Baud rate
19200
Parity
None
Data bits
8
Stop bits
1
Flow control
None
CHAPTER 4
VAISALA INDUSTRI AL PROTOCOL
This chapter describes the Vaisala Industrial Protocol implementation of
the GMP231.
Overview
RS-485 line of the GMP231 provides an implementation of the Vaisala
Industrial Protocol that can be used for service and configuration use, or
for interfacing with the incubator’s control system. The protocol is a
plaintext protocol suitable for use both by human operators and
automated systems.
Table 6 Default Serial Interface Settings
Physical Interface
The physical interface is a non-isolated 3-wire interface. The data lines
are RS-485 D- and RS-485 D+. Ground is shared with power supply.
The connector is an 8-pin male M12. For connector pinout and wiring
information, see section Wiring on page 24.
VAISALA ________________________________________________________________________ 25
Loading...