USER'S GUIDE Vaisala CARBOCAP® Carbon Dioxide Probe GMP231 M211501EN-C
PUBLISHED BY Vaisala Oyj Street address: Mailing address: Phone: Fax: Vanha Nurmijärventie 21, FI-01670 Vantaa, Finland P.O. Box 26, FI-00421 Helsinki, Finland +358 9 8949 1 +358 9 8949 2227 Visit our Internet pages at www.vaisala.com.
_________________________________________________________________________________ Table of Contents CHAPTER 1 GENERAL INFORMATION ............................................................................ 7 About This Manual ................................................................... 7 Contents of This Manual ....................................................... 7 Version Information ............................................................... 8 Related Manuals .............................
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 ....
_________________________________________________________________________________ Communication Flow ............................................................. 52 GMP231 State Machine ...................................................... 53 Examples of Communication Flow ...................................... 54 Timing.................................................................................. 56 Status Byte .......................................................................... 56 Checksum ...
User's Guide _______________________________________________________________________ Analog Output Error State ..................................................... 84 Technical Support .................................................................. 84 Product Returns...................................................................... 84 CHAPTER 9 TECHNICAL DATA ...................................................................................... 85 Specifications ....................................
_________________________________________________________________________________ List of Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 Figure 22 Figure 23 Figure 24 Figure 25 Figure 26 Figure 27 Figure 28 Figure 29 Figure 30 GMP231 Installed Through a Chamber Wall (Example) .......... 12 GMP231 Parts ............................................
User's Guide _______________________________________________________________________ List of Tables Table 1 Table 2 Table 3 Table 4 Table 5 Table 6 Table 7 Table 8 Table 9 Table 10 Table 11 Table 12 Table 13 Table 14 Table 15 Table 16 Table 17 Table 18 Table 19 Table 20 Table 21 Table 22 Table 23 Table 24 Table 25 Table 26 Table 27 Table 28 Table 29 Table 30 Table 31 Table 32 Table 33 Table 34 Table 35 Table 36 Table 37 Table 38 Table 39 Table 40 Table 41 Table 42 Table 43 Table 44 Table 45 Table 46 Manua
Chapter 1 _________________________________________________________ General Information CHAPTER 1 GENERAL INFORMATION 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 Information, provides general notes for the manual and the GMP231 probe.
User's Guide _______________________________________________________________________ Version Information Table 1 Manual Code M211501EN-C M211501EN-B M211501EN-A Manual Revisions Description May 2014. This manual. Updated description for ENV command in section Change Compensation Setpoint Values on page 36. Previous version. Applicable from software version 1.1.0 onward. Added instructions for operation with the MI70 hand-held indicator.
Chapter 1 _________________________________________________________ General Information Safety The GMP231 probe delivered to you has been tested for safety and approved as shipped from the factory. Note the following precautions: WARNING 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. CAUTION Do not modify the unit. Improper modification can damage the product or lead to malfunction.
User's Guide _______________________________________________________________________ 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.
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.
User's Guide _______________________________________________________________________ CHAPTER 2 PRODUCT OVERVIEW 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.
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.
User's Guide _______________________________________________________________________ GMP231 Parts 1 2 3 6 7 8 5 4 1403-153 Figure 2 CAUTION GMP231 Parts 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 screw depth 8 mm. Two screws included, type 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.
Chapter 2 ___________________________________________________________ Product Overview 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.
User's Guide _______________________________________________________________________ 2 1 3 4 5 6 7 8 9 10 1403-161 Figure 4 1 2 3 4 5 6 7 8 9 CO2 Measurement Inside the Incubator = = = = = = = = = Chamber wall. Chamber interior. Light source. Band pass filter. Ambient air (400 ... 1000 ppm CO2). Light absorbed by CO2 in the incubator gas. Thermopile detector. Fabry-Perot interferometer. Sapphire window. Separates the sensor’s active components from the measured environment.
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.
User's Guide _______________________________________________________________________ Background Gas Compensations 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.
Chapter 2 ___________________________________________________________ Product Overview 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.
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.
Chapter 3 ________________________________________________________________ Installation 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.
User's Guide _______________________________________________________________________ Dimensions 163 11 118.5 Ø 19 Screw BN 10649 M4 x 8 mm (for 1 mm thick sheet metal attachment) Ø 24.8 1.3° Ø 30.2 21 Position only the filter inside the heated chamber 1403-108 Figure 6 Probe Dimensions without Silicone Plug 163 11 118.5 2.5 Ø 19 1.3° Ø 30.
Chapter 3 ________________________________________________________________ Installation 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.
User's Guide _______________________________________________________________________ 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).
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol CHAPTER 4 VAISALA INDUSTRIAL 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.
User's Guide _______________________________________________________________________ Connecting with a Computer Connecting with a computer allows you to configure and troubleshoot your probe using serial line commands. For a list of commands, see section Serial Commands on page 28.
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol Terminal Application Settings The steps below describe how to connect to the probe using the PuTTY terminal application for Windows (available for download at www.vaisala.com) and a USB computer connection cable: 1. 2. 3. 4. 5. NOTE Connect the USB serial interface cable between your PC and the M12 connector of the probe. Start the PuTTY application.
User's Guide _______________________________________________________________________ Serial Commands All commands can be issued either in uppercase or lowercase. In the command examples, the keyboard input by the user is in bold type. The notation refers to pressing the carriage return (Enter) key on your computer keyboard. Enter a to clear the command buffer before starting to enter commands. Table 7 Basic Serial Commands Command ? CLOSE ECHO ENV ERRS FORM [modifier string] HELP INTV [0 ...
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol Table 8 Advanced Serial Commands Command ADDR [0 … 254] AMODE AOVER ASEL ATEST CCO2 CDATE CP CT CTEXT FRESTORE O2CMODE PCMODE RHCMODE TCMODE Description Show or set probe address. Show or set analog output mode. Show or set analog output overrange and clipping behavior. Show or set analog output parameter. Test analog putput. Adjust CO2 measurement gain and offset. Show or set calibration date.
User's Guide _______________________________________________________________________ Show Serial Number SNUM Example: snum Serial number : J1320082 Show Firmware Version VERS Example: vers GMP231 / 1.1.0.1537 Show Firmware Information SYSTEM Example: system Device Name SW Name SW version : GMP231 : GMP231 : 1.1.0.1537 Show Probe Uptime Use the TIME command to show how long the probe has been in operation, and what is the current uptime since last reset (in seconds).
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol Show Command List Use the HELP command to show a list of the currently available serial commands.
User's Guide _______________________________________________________________________ Stop Measurement Output You can stop the measurement output by pressing the ESC key or with the S command. Set Output Interval Use the INTV command to change the output interval of the automatically repeating measurement messages. The measurement messages are repeated in the RUN mode, or after the R command has been given. INTV [n xxx] where n xxx = = time interval, range 0 ...
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol Set Measurement Output Format Use the serial line command FORM to change the measurement message sent by the probe. You can freely define the output message to include the desired parameters, formatting options, text strings, and additional fields. FORM [modifier string] where modifier string = String of parameters and modifiers that defines the output format, length 1 ... 150 characters.
User's Guide _______________________________________________________________________ FORM Command Examples Example of default output (continuous output from RUN mode): CO2= CO2= CO2= ... 860 ppm 861 ppm 861 ppm Command to set output format as %CO2: form 3.1 "CO2=" CO2% " " U4 #r #n Output example: CO2= CO2= CO2= ... 5.1 %CO2 5.1 %CO2 5.0 %CO2 Command to set output format as CO2 ppm with Modulus-65536 checksum: form 6.0 "CO2=" CO2 " " U3 " " CS4 #r #n Output example: CO2= CO2= CO2= ...
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol Changing Measurement Settings Set Compensation Modes You can change the mode of each environmental compensation type using a dedicated serial command. The commands are: - PCMODE for pressure compensation mode. TCMODE for temperature compensation mode. O2CMODE for oxygen compensation mode. RHCMODE for relative humidity compensation.
User's Guide _______________________________________________________________________ Change Compensation Setpoint Values Use the ENV command to show or set the setpoint values of the environmental compensation parameters. To change a value, give the parameter name and value as arguments to the ENV command. ENV [temp|pres|oxy|hum|xtemp|xpres|xoxy|xhum] [value] There are four compensation parameters.
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol Example below sets temperature compensation to setpoint mode, and changes temperature setpoint value to 37.2 in RAM. pass 1300 tcmode on T COMP MODE env xtemp 37.2 In eeprom: Temperature (C) Pressure (hPa) Oxygen (%O2) Humidity (%RH) In use: Temperature (C) Pressure (hPa) Oxygen (%O2) Humidity (%RH) NOTE : ON : : : : 37.00 1013.20 19.70 93.00 : : : : 37.2 1013.20 19.70 93.
User's Guide _______________________________________________________________________ Configuring Serial Line Operation Set Serial Line Operating Mode Use the SMODE command to set the start-up operating mode of the serial line. SMODE [mode] where mode = STOP, RUN, or POLL. Table 11 Mode STOP RUN POLL Selection of Output Modes Measurement Output Only with the SEND command. Automatic output. Only with the SEND [addr] command. Available Commands All (default mode). Only command S.
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol Set Serial Line Settings Use the SERI command to set the serial line settings. The new settings will be taken into use when the probe is reset or powered up.
User's Guide _______________________________________________________________________ Set Serial Line Response Time With the SDELAY command you can set delay (response time) of the serial line, or view the currently set delay value. SDELAY [delay] where delay = Serial line delay, range 0 … 255 (milliseconds). Example (set delay to 50 milliseconds): sdelay 50 Serial delay : 50 Set Serial Line Echo Use the ECHO command to enable or disable the echoing of characters received by the probe.
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol Calibration Commands NOTE Before calibrating GMP231 using serial line commands, read the instructions in section Calibration and Adjustment on page 73. Make sure that the environmental compensation settings of the GMP231 are properly set for your calibration environment; see section Changing Measurement Settings on page 35. Adjust CO2 Measurement Use the CCO2 command to adjust CO2 measurement in one or two points.
User's Guide _______________________________________________________________________ Example (show current user adjustment status – no adjustment done): pass 1300 cco2 1.Ref. point low 0 1.Meas. point low 0 2.Ref. point low 200000 2.Meas. point low 200000 Gain : 1.0000 Offset : 0.0000 Example (one-point adjustment in 5% concentration (50000 ppm)): pass 1300 cco2 –lo 50000 OK cco2 –save OK Set Calibration Date Use the CDATE command to view the date when the probe was last calibrated, or set a new date.
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol Set Calibration Info Text Use the CTEXT command to view or set calibration information text. CTEXT [text] where text = Calibration information text string, max 19 characters. If you want to use spaces in the string, enclose the text in quotes.
User's Guide _______________________________________________________________________ Adjust Pressure Measurement Use the CP command to perform an offset correction to the internal pressure measurement. The correction is done by providing the correct pressure as an argument to the CP command. CP [pressure] CP [-reset] where pressure = Correct pressure in hectopascals (hPa).
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol Configuring Analog Output Set Analog Output Scaling Use the ASEL command to show or set the scaling of the analog output. ASEL [channel] [parameter lowlimit highlimit] where channel = Analog output channel, only 1 can be selected. parameter = Parameter that is output on analog channel. Only parameter available is CO2. lowlimit = Lower limit of channel scaling in ppm.
User's Guide _______________________________________________________________________ Set Analog Output Clipping and Error Limit Use the AOVER command to define the behavior of the analog output when the measured value is outside the scaled output range. AOVER [channel clip% valid%] where channel = Analog output channel, only 1 can be selected. clip% = Output margin (%) at which the output is clipped. valid% = Output margin (%) at which the output of the channel goes into the error state.
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol Test Analog Output You can test the operation of the analog output with the ATEST command by forcing the output to a given value. You can then measure the output with a calibrated multimeter. After testing the output, use the ATEST command again to exit the test mode. ATEST [channel] [level] where channel level = Analog output channel, only 1 can be selected. = Level for analog output channel in mA.
User's Guide _______________________________________________________________________ Connecting to Probe in POLL Mode Use the OPEN command to connect to a probe that is in POLL mode. OPEN [address] where address = Probe address, range 0 ... 254. Example (target probe in POLL mode, with address 52): open 52 GMP231: 52 Opened for operator commands Closing the Connection to a Probe in POLL Mode The CLOSE command closes the connection to a probe.
Chapter 4 ____________________________________________________ Vaisala Industrial Protocol Reset Probe Use the RESET command to reset the probe. RESET When the RESET command is given, the probe will restart as if it had just been powered on. Restore Factory Settings Use the FRESTORE command to restore the probe to its factory configuration. All user settings will be lost. FRESTORE NOTE After using the FRESTORE command, reset the probe using the RESET command.
User's Guide _______________________________________________________________________ CHAPTER 5 I2C INTERFACE This chapter describes the I2C interface implementation of the GMP231. Overview GMP231 has an inter-integrated circuit (I2C) interface for interfacing with the incubator’s control computer. GMP231 implements I2C slave functionality, with the incubator’s computer acting as the master.
Chapter 5 _______________________________________________________________ I2C Interface Communication Parameters GMP231 supports maximum 50 kHz clock speed. Protocol bits are sent most significant bit (MSB) first. Parameter bytes are sent using little endian order. Addressing GMP231 uses 7-bit addressing. The address consists of: - 4-bit device type identifier part (default “0001” for GMP231) - 3-bit sub address (default “001”) The full 7-bit default address is “0001001” (09h).
User's Guide _______________________________________________________________________ Communication Flow Basic communication flow always includes I2C write and read commands. First the master writes a command to the slave device, and then the master reads the results of that command from the slave. When the master reads data from the slave, there is an ACK/NACK-bit in the status byte that informs the master whether or not communication was success.
Chapter 5 _______________________________________________________________ I2C Interface Table 15 Response Message in GMP231 I2C Interface Message Segment Start 2 I C address Status Command Device address Frame length Data Checksum Stop Length Content 2 I C start condition. 1 byte See Table 12 on page 51. 1 byte See section Status Byte on page 56. 1 byte Identifier of command that was used in the invoke that the slave is responding to.
User's Guide _______________________________________________________________________ Response NACK Idle Valid Invoke Response ACK + data Bad Invoke Response NACK Bad Invoke Wait Response Valid Invoke 1403-146 Figure 13 GMP231 State Machine Examples of Communication Flow The basic data transfer communication flows are presented in the figures below. Each arrow represents an I2C read or write operation The examples are simplified presentations. For actual message content, see section Commands on page 58.
Master Set_Parameter,Pressure_ID,1013.
User's Guide _______________________________________________________________________ Timing The minimum time delay that the master must wait between the invoke and response messages depends on the operation. If the operation includes a write to the non-volatile memory, it takes more time than other operations.
Chapter 5 _______________________________________________________________ I2C Interface Status Word The status word is used to monitor the status of the GMP231 device. It can be read in the same way as any other slave parameter. The status word is used as a 32-bit long bit field, where each bit represents a state of some error or other essential status. Changes in the status word bits can be monitored by reading the status byte. See section Status Byte on page 56.
User's Guide _______________________________________________________________________ Commands Get_Interface_Version Get_Interface_Version command (ID 80h) reads the interface version information. This command is recommended for verifying version compatibility before reading or writing parameters.
Chapter 5 _______________________________________________________________ I2C Interface Get_Parameter Get_Parameter command (ID 81h) reads parameter values. You can use it to read both measurement results and operational parameters. If the master tries to read more bytes than message size, the slave sends FFh bytes.
User's Guide _______________________________________________________________________ Example: Read CO2 Measurement Result Table 23 Get_Parameter Invoke Message Example Message Bytes (hex) 12 81 09 06 0A AA 9F Table 24 Content 2 I C address Get_parameter command Device address Frame length CO2 Parameter ID CRC high CRC lo Get_Parameter Response Message Example Message Bytes (hex) 13 00 81 09 0B 0A 69 68 23 44 75 7D Content 2 I C address Status byte (no errors, ACK) Get_parameter command Device addres
Chapter 5 _______________________________________________________________ I2C Interface Set_Parameter Set_Parameter command (ID 82h) writes parameter values to nonvolatile memory. You can use it to set the operational parameters of the GMP231. Depending on the change, the functionality of the GMP231 may not change immediately. The length of the invoke message varies depending on the data length. The master must write as many bytes as indicated in the frame length of the invoke message.
User's Guide _______________________________________________________________________ Example: Set Compensation Temperature Table 28 Example Set_Parameter Invoke Message Message Bytes (hex) 12 82 09 0A 10 00 00 14 42 0C 6E Table 29 Content 2 I C address Set_parameter command Device address Frame length Parameter ID of compensation temperature Temperature 37C CRC high CRC lo Example Set_Parameter Response Message Message Bytes (hex) 13 04 82 09 08 10 00 D1 CE Content 2 I C address Status byte (error
Chapter 5 _______________________________________________________________ I2C Interface Get_Parameter_Info Get_Parameter_Info command (ID 83h) reads the properties of a single parameter from the GMP231. The command is useful for adapting to parameters that have been added in a new software version. If the requested parameter ID is not valid, data type Unknown Parameter ID is returned.
User's Guide _______________________________________________________________________ Adjust Adjust command (ID 84h) controls the user adjustment sequence of CO2 measurement.
Chapter 5 _______________________________________________________________ I2C Interface Table 38 Code 0 1 2 3 4 5 Adjustment Return Codes Meaning Ok Function not supported Sequence error Recorded-Reference difference too large 2-point adjustment: Points too close Given reference value is invalid Adjusting Measurement NOTE Before implementing an adjustment sequence using the Adjust command, read the general instructions for calibration and adjustment in section Calibration and Adjustment on page 73.
User's Guide _______________________________________________________________________ Two Point Adjustment To perform a two point adjustment of CO2 measurement using I2C protocol, you must perform the following sequence: 1. 2. 3. 4. 5. 6. Using the Adjust command, start 2 point adjustment for CO2. Supply the low concentration CO2 reference gas to the sensor and wait for three minutes until the measurement has stabilized.
Chapter 5 _______________________________________________________________ I2C Interface Register Table Table 40 Meaning Name Factory information Device address ADDR Device serial number SNUM Sensor number SSNUM Component board CBNUM number Software version number VERS Factory adjustment date ADATEY Year Factory adjustment date ADATEM Month Factory adjustment date ADATED Day General parameters and variables GMP231 Register Table ID Size (bytes) Type Read/ Write Persistent Other 0 1 2 3 1 12 12 12
User's Guide _______________________________________________________________________ Meaning Name ID Size (bytes) Type Read/ Write Persistent Other Temperature compensation mode TC_MODE 15 1 Byte R/W Yes Compensation temperature Measured temperature (internal sensor) Pressure compensation mode T_COMP 16 4 Float R/W No 0 = Compensation off 1 = Use temperature setpoint value (default) 2 = Use Internal sensor temperature Celsius T 17 4 Float R No Celsius PC_MODE 18 1 Byte R/W
Chapter 5 _______________________________________________________________ I2C Interface Meaning Name ID Size (bytes) Type Read/ Write Persistent Other Yes 37 °C (default) Yes Yes Yes 1013.25 hPa (default) 90 %RH (default) 19.
User's Guide _______________________________________________________________________ CHAPTER 6 MAINTENANCE This chapter provides information that is needed in the basic maintenance of the GMP231. Cleaning When correctly installed, the GMP231 is minimally exposed to contaminants in the chamber. There is little reason to perform cleaning other than normal chamber sterilization, and changing the filter and/or silicone plug if they appear contaminated.
Chapter 6 _______________________________________________________________ Maintenance Changing the Filter Change the filter to a new one if it shows visible signs of contamination. 1. 2. 3. Pull the white PTFE filter away from the sensor. Rotating the filter slightly makes it easier to detach. Use clean instrument air to gently blow any loose dirt and filter material away from the sensor. Take a new clean filter and push it onto the sensor.
User's Guide _______________________________________________________________________ Changing the Silicone Plug Change the silicone plug if it shows visible signs of contamination. It is best to replace the filter also. 1. 2. 3. 4. 5. 6. Pull the white PTFE filter away from the sensor. Rotating the filter slightly makes it easier to detach Lift one edge of the plug and pull it away from the installation tube. Use clean instrument air to gently blow any loose dirt and filter material away from the sensor.
Chapter 6 _______________________________________________________________ Maintenance Calibration and Adjustment Calibrate and adjust the CO2 measurement of the GMP231 as needed. Before starting, read through this section completely so that you are aware of your options, and the main factors that affect the result. NOTE Performing an accurate calibration and adjustment takes some time and preparation.
User's Guide _______________________________________________________________________ Using Ambient Air as Reference You can use ambient air to do a 1-point calibration with the background CO2 level as your reference. You will need a calibrated reference instrument to compare against, for example a GM70 hand-held meter with a calibrated GMP222 probe.
Chapter 6 _______________________________________________________________ Maintenance - The effect of background gas compensations for humidity and oxygen may be significant when using calibration gases, since they are often dry and oxygen-free. For example, pure nitrogen gas is typically used as a convenient 0 ppm CO2 reference. - Remember to restore the normal compensation settings after completing calibration and adjustment.
User's Guide _______________________________________________________________________ I2C Interface I2C interface supports one and two-point adjustment sequences as well as configuration of the environmental compensation settings using the Get_Parameter and Set_Parameter commands. See the following sections: - Adjust on page 64 - Get_Parameter on page 59 - Set_Parameter on page 61 Vaisala Industrial Protocol Vaisala industrial protocol supports one and two-point adjustment with the CCO2 command.
Chapter 7 _________________________________________________ Operating with MI70 Indicator CHAPTER 7 OPERATING WITH MI70 INDICATOR Overview of MI70 Support GMP231 is compatible with instruments that utilize the MI70 Indicator, for example the GM70 Hand-Held Carbon Dioxide Meter. The MI70 indicator is a convenient service tool for viewing the measurement readings, adjusting the environmental compensation settings, and performing calibration and one-point adjustment.
User's Guide _______________________________________________________________________ Changing Environmental Compensation Settings with MI70 Indicator You can see the compensation values that are currently used by the GMP231 by selecting them as display quantities from Main menu > Display > Quantities and Units. The quantities are as follows: - Tcomp: currently active temperature compensation value. Pcomp: currently active pressure compensation value.
Chapter 7 _________________________________________________ Operating with MI70 Indicator Calibration and Adjustment with MI70 Indicator NOTE Before using the MI70 indicator for calibration and adjustment, read the instructions in section Calibration and Adjustment on page 73. Make sure that the environmental compensation settings of the GMP231 are properly set for your calibration environment; see section Changing Environmental Compensation Settings with MI70 Indicator on page 78.
User's Guide _______________________________________________________________________ 7. 8. 9. To proceed with the adjustment, select the CO2(I) parameter in the Select Quantity screen. In the Select Quantity screen you can also view the currently used compensation values, and the Last adjustment date information. You can update the date and text using the CDATE and CTEXT commands on the serial line. You may be prompted to check the environmental settings of the reference probe before proceeding.
Chapter 7 _________________________________________________ Operating with MI70 Indicator 1-Point Adjustment with a Reference Gas 1. 2. 3. 4. Connect the GMP231 to Port I of the MI70 indicator. Feed a calibration gas to the GMP231 using the calibration adapter accessory. If you are using ambient air as the calibration gas, you must have a reference meter in the same environment to verify the CO2 concentration. Turn on the MI70 indicator.
User's Guide _______________________________________________________________________ 1403-126 Figure 29 10. 11. 12. Selecting the Adjustment Mode You will be prompted if you really want to adjust. Select Yes. You are now in the 1-point adjustment screen. Allow the measurement to stabilize and press Ready. Enter the CO2 concentration of the reference gas and press OK. 1403-125 Figure 30 13. 14. Entering the Reference CO2 Concentration You will be prompted if you really want to adjust. Select Yes.
Chapter 8 ____________________________________________________________ Troubleshooting CHAPTER 8 TROUBLESHOOTING This chapter describes possible problems, their probable causes and remedies, and provides contact information for technical support. Problem Situations Table 41 Possible Problem Situations and Their Remedies Problem Analog output reading is unchanging and appears incorrect. Probe outputs stars "****" on serial line instead of measurement data.
User's Guide _______________________________________________________________________ Analog Output Error State GMP231 sets the analog output channel into a defined error level instead of the measured result in two situations: - Probe detects a measurement malfunction. This means an actual measurement problem, such as sensor damage or unsuitable environmental conditions. - Measured value(s) are well outside the scaled output range.
Chapter 9 _____________________________________________________________ Technical Data CHAPTER 9 TECHNICAL DATA This chapter provides the technical data of the GMP231. Specifications Table 42 Performance Property Measurement range Accuracy at 37 °C, 1013 hPa Repeatability at 0 ... 8 %CO2 Repeatability at 8 ... 12 %CO2 Repeatability at 12 ... 20 %CO2 Non-linearity at 0 ...
User's Guide _______________________________________________________________________ Table 43 Operating Environment Property Operating temperature of CO2 measurement Max.
Chapter 9 _____________________________________________________________ Technical Data Spare Parts and Accessories Table 46 Spare Parts and Accessories for GMP231 Description M12 Connection Cable 0.9 m with open ends M12 Connection Cable 0.
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