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1 TECHNICAL INFORMATION FOR K30 CO2 MODULE an ISO9001/14001 company Technical Information for the K30 CO2 Sensor Module The K30 sensor platform CO 2 Module can be customized for a variety of sensing and control applications. This platform is designed to be an OEM module for built-in applications in a host apparatus. Users can optimize the module usage through communications with Figaro USA Inc. Page Introduction...2 Basic Structure and Specifications Terminal descriptions...2 Specifications...2 Default Functions and Configurations Outputs...2 Calibration...4 Zero calibration procedure...6 Self diagnosis...6 Installation Installation options...7 Host intergations considerations and EMI shielding...7 Maintenance...8 Warranty and Limitation of Liability...8 Revised 05/08 1

2 1. Introduction The K30 sensor module is a low cost, maintenancefree infrared transmitter module intended to be built into host devices that require CO2 monitoring data. The K30 is intended for high volume production. For a moderate startup charge, the module can also be provided with tailor-made features to meet a customer s unique requests. Suitable applications for the K30 include fresh air ventilators, air conditioning and air cleaners in car cabins and buildings, appliances such as kitchen fans, automatic window openers, combustion controls, etc. 2. Basic Structure and Specifications The basic structure of the module can be seen in Figs. 1 and 2, and the dimensions of the device are shown in Fig Terminal descriptions Table 1 (opposite page) specifies the terminals and I/O options which are available in the general K30 platform (see also the structure shown in Fig. 1). Please note, however, that in the K30-STA default configuration, only OUT1, OUT2, OUT3, OUT4, Din1, Din2 and Status have any pre-programmed functions. These are described in Item 3-Default Functions and Configurations. 2-2 Specifications Please refer to Figure 4 (page 5). 3. Default Functions and Configurations 3-1 Outputs The basic K30-STA configuration is a simple analog output sensor transmitter signal directed to OUT1 and OUT2. Via the edge connector serial communication terminal, CO2 readings are available with an even higher precision (Modbus protocol), together with additional system information such as sensor status, analog outputs, and other variables. Fig. 1 - K30 Module structure (top view). The blue filled pins are defined by default. test/sample gas ports Fig. 2 - K30 Module OBA position Revised 05/08 2

3 Power supply Functional group Table 1 - K30 Module terminals Description and ratings G+ referred to G0 Absolute maximum rating: 4.5 ~ 14V, stabilized to within 10% Preferred operating range: 4.5 ~ 9V CAUTION: Unprotected against reverse connection Serial Communication UART (TxD, RxD) Outputs OUT1 OUT2 OUT3 OUT4 Status Inputs Din0, Din1, Din2, Din3, Din4 Optional jumper field Din0, Din1, Din2, Din3, Din4 I 2 C extension Contact Figaro for information CMOS, ModBus communication protocol Logical levels correspond to 3.3V powered logics. Refer to "ModBus on CO2 Engine K30 for electrical specification. Buffered linear output = 0.4, 1.4, 0.10, or 2.1V DC, depending on specified power supply and sensor configuration. ROUT < 100 Ω, RLOAD > 5 kω CAUTION: Load to ground only Resolution: 10mV (8.5 bits in the range of 0.4V). Buffered linear output = 0.4, 1.4, 0.05, or 1.5V DC, depending on specified power supply and sensor configuration. ROUT < 100 Ω, RLOAD > 5 kω CAUTION: Load to ground only Resolution: 5mV Can be used as alternative for OUT1, or for a second data channel, or in an independent linear control loop (such as housing temperature stabilization) CMOS unprotected Digital (High/Low) output High Output level: in the range 2.3V min to DVDD = 3.3V (1mA source) Low output level: 0.75V max (4mA sink) Can be used for gas alarm indication, status indication, etc. CMOS unprotected Digital (High/Low) output High Output level: in the range 2.3V min to DVDD = 3.3V (1mA source) Low output level: 0.75V max (4mA sink) Can be used for gas alarm indication, status indication, etc. CMOS unprotected High Output level: in the range 2.3V min to DVDD = 3.3V (1mA source) Low output level: 0.75V max (4mA sink) Digital switch inputs, pull-up 120k to DVCC 3.3V. Driving these inputs Low or connecting to ground G0 activates input. Pull-up resistance is decreased to 4.10k during read of input or jumper. Advantages are lower current consumption most of the time the input/jumper is kept low and larger current for jumpers read in order to provide cleaning of the contact. Depending on user's needs, these inputs can be used to initiate calibration, switch output range, or force output to a predefined state. Digital switch inputs, pull-up 120k to DVCC 3.3V. Connecting to ground G0 activates input. Pull-up resistance is decreased to 4.10k during read of input or jumper. Advantages are lower current consumption most of the time the input/jumper is kept low and larger current for jumpers read in order to provide cleaning current. These are the same as inputs on the IDC connector. Depending on user's needs, these inputs can be used to initiate calibration, switch output range, or force output to a predefined state. Pull-up of SDA and SCL lines to 3.3V. Revised 05/08 3

4 Fig. 3 - K30 Module dimensions Terminal Output Corresponding CO2 concentration OUT1 0.0~4.0V DC 0~2000ppm OUT2 1.0~5.0V DC 0~2000ppm The basic CO2Engine K30-STA configuration provides digital outputs to indicate if CO2 concentration exceeds the alarm threshold. Terminal OUT3 OUT4 3-2 Calibration Table 2 - Default analog output for K30-STA Output Logical levels: Low <0.75V 2.3V < High < 3.3V Logical levels: Low <0.75V 2.3V < High < 3.3V Corresponding CO2 concentration OUT3 OUT4 700/800ppm 900/1000pm Table 3 - Default digital output for K30-STA CO2 level CO2 level The default sensor OEM unit is maintenance-free in normal environments thanks to the built-in self correcting ABC (Automatic Baseline Correction) algorithm. This algorithm constantly keeps track of the sensor s lowest reading over a 7.5 day interval and slowly corrects for any long-term drift detected as compared to the expected fresh air value of 400 ppm CO2. Rough handling and transportation may cause a reduction of sensor reading accuracy. Over time, the ABC function will tune the readings back to the correct value. The default tuning speed is limited to about 30ppm/week. For post calibration convenience, in the event that one cannot wait for the ABC algorithm to cure any calibration offset, two switch inputs (Din1 and Din2) are defined for the operator to select one out of two prepared calibration codes. If Din1 is shorted to ground for a minimum time of 8 seconds, the internal calibration code bcal (background calibration) is executed, in which case it is assumed that the sensor is operating in a fresh air environment (400ppm CO2). If Din2 is shorted for a minimum time of 8 seconds, the alternative operation code CAL (zero calibration) is executed, in which case the sensor must be purged by some gas mixture which is free from CO2 (i.e. Nitrogen or Soda Lime CO2 scrubbed air). If unsuccessful, please wait at least Revised 05/08 4

5 Category Item Specification General Performance Storage Temperature -30 ~ +70 C Sensor Life Expectency > 15 years Maintenance Interval no maintenance required (note 1) Self Diagnostics complete function check of sensor module Warm-up Time 1 minute (@full spec 15 min.) Emissions: EN :2001 Conformance with Standards Immunity: EN :2001 RoHS directive 2002/95/EG Operating Temperature 0 ~ 50 C Electrical / Mechanical CO2 Measurement (note 4) Operating Humidity Operating Environment Power Input Current Consumption Electrical Connections (note 4) Dimensions Sensing Method Sampling Method Response Time (T 1/e ) Measurement Range Sensitivity Accuracy (note 1) Pressure Dependency 0 ~ 95%RH (non-condensing) Residential, commercial, industrial spaces HVAC systems (notes 2,4) V DC, stabilized to within ±10% (external protection circuit required) (note 3) 40mA average < 150mA peak current (avg during IR lamp ON, 110 msec) < 300mA peak power (during IR lamp start-up, first 35msec.) terminals not mounted (G+, G0, OUT1, OUT2, ErStat, TxD, RxD) 5.1cm length x 5.7cm width x 1.4cm height non-dispersive infrared (NDIR) waveguide technology with ABC (automatic background calculation) algorithm diffusion (optional: tube in/out) 20 sec. diffusion time 0 ~ 2000ppm (0 ~ ppm extended) ±20ppm ±1% of measured value ±30ppm ±5% of measured value +1.6% reading per kpa deviation from normal pressure of 100kPa Linear Signal Output (notes 4,5,6,7) Digital Outputs (notes 4,7) UART Serial Com Port (note 4) OUT1 OUT2 On-board Calibration Support D/A Conversion Accuracy Electrical Characteristcs D/A Resolution Din1 switch input to trigger Background 400ppm CO2 Din2 switch input to trigger Zero 0ppm CO2 ±2% of reading ±20mV 10mV Linear Conversion Range 0~4V DC (note 7) Electrical Characteristics D/A Resolution Rout < 100Ω, Rload > 5kΩ 5mV Linear Conversion Range 1~5V DC (note 7) Electrical Characteristics Function High Output Low Output OUT3 CO2 High Alarm/Reset Level OUT4 CO2 High Alarm/Reset Level Protocol Hardware Interface Baud Rate Rout < 100Ω, Rload > 5kΩ 2.3V min. to DVDD=3.3V (1mA source) 0.75V max. (4mA sink) - protection 56R in series High level at CO2 High 800/700 ppm 1000/900 ppm MODBUS open protocol CMOS UART with RxD (R/T to support RS485 standard drivers on request) 9600 (max. TBD) Note 1: In normal IAQ applications, accuracy is defined after a minimum 3 weeks of continuous operation. However, some industrial applications do require maintenance. Please contact Figaro for further information. Note 2: SO2 enriched environments are excluded. Note 3: Notice that absolute maximum rating is 14V, so the sensor can be used with 12V±10% supply Note 4: Different options exist and can be customized depending on the application. Please contact Figaro for further information. Note 5: During power up, OUT1 and OUT2 are defined to be low. Exact value depends on many factors including temperature. Note 6: For the buffered outputs OUT1 and OUT2 the maximum output voltage range equals power voltage input minus 0.5 V Note 7: Can be configured with optional configure tool Fig. 4 - K30 Module specifications Revised 05/08 5

6 TECHNICAL INFORMATION FOR K30 CO2 MODULE 10 seconds before repeating the procedure again. The sensor environment must be stable and calm. Refer to Item 3-3 Zero calibration procedure. Input Switch Terminal (normally open) Default Function (when closed for 8 sec miimum) Din1 bcal (background calibration) assuming 400ppm CO2 Din2 CAL (zero calibration) assuming 0ppm CO2 Table 4 - Default switch input for K30-STA 3-3 Zero calibration procedure 1) Connect the sensor on top with a tube (soft tubing 2x4 mm) and a nipple (nylon tubing 30x0.8x2.2 mm), as shown in Figure 5. There are 2 alternative positions for nipple attachment. 2) Let a gas mixture flow into the sensor through the applied tube. The flow shall be in the range of 0.3~1.0 liter/min. for a duration of 3 minutes. Keep the gas mixture flowing during the whole procedure. 3) Short circuit Din2 for a minimum of 8 seconds. 4) Verify zero calibration. The meter should show 0ppm CO2. 5) If zero calibration is not properly executed (i.e. the sensor detected an unstable gas concentration), wait 10 seconds and repeat steps 3 and 4 again. CAUTION: Do not breathe on the sensor. Figure 5 - K30 with connected tube 3-4 Self diagnosis The system contains complete self-diagnostic procedures. A full system test is executed automatically every time the power is turned on. In addition, as an ongoing process during operation, the sensor probes are monitored for failure by checking the valid dynamic measurement ranges. All EEPROM updates, initiated by the sensor itself as well as by external connections, are checked by subsequent memory read back and data comparisons. These various system checks will return error bytes to the system RAM. If this byte is not zero, the logic output terminal Status will be put into Low level state. Full error codes are available from the UART port or via I2C communication. Offset regulation error and Out of Range are the only bits that are reset automatically after return to a normal state. All other error bits have to be reset after return to normal by UART overwrite or by powering off/on. Output Terminal Staus Default Function High = OK Low = Fault Table 5 - Default logic output for K30 Module Revised 05/08 6

7 Bit# Error Code 0 1 Fatal error 1 2 Offset regulation error Error Description Algorithm error Indicates wrong EPROM configuration Output error Error detected during output signal calculation and generation Self-diagnosis error May indicate need of zero claibration or sensor replacement Out of range error Covers most other errors. May also indicate overload or failure of sensor and inputs. Resets automatically after source of error disappears. Memory error Error during memory operations Reserved - Suggested Action Try to restart sensor by powering OFF/ON. If unsuccessful, contact Figaro. Try to restart sensor by powering OFF/ON. If unsuccessful, contact Figaro. Try to restart sensor by powering OFF/ON. Check detailed settings and configuration with software tools. If unsuccessful, contact Figaro. Check connections and output loads. Check detailed status of outputs with software tools. Check detailed self diagnostic status with software tools. If unsuccessful, contact Figaro. Check connections of temperature and relative humidity probe (if mounted). Try sensor in fresh air. Perform CO2 background calibration. Check detailed status of measurements with software tools. Please refer to Note 1. Check detailed settings and confoguration with software tools. Table 6 - Error Codes (readable via one of the communication channels) NOTE 1: Any probe is out of range. Occurs, for instance, during over-exposure of CO2 sensor, in which case the error code will automatically reset when the measurement values return to normal. Could also indicate the need of zero point calibration. If the CO2 readings are normal, and still the error code remains, another sensor probe(s) mounted (if any) may be defective, or the connection to this probe is broken. Remark: If several errors are detected at the same time, different error code numbers will be added together into a single error code. 4 Installation 4-1 Installation options Modules are factory calibrated and ready for use immediately after power up. There are several alternative ways to connect the K30 Module to a host system (see also Figure 1): CAUTION--Do not use edge connectors for connecting to the host system without discussing with Figaro. 1. Using an UART connector, including terminals for power supply (G+ and G0), UART (TxD, RxD). 2. Using the 3 pin main terminals. Available signals are power supply (G+ and G0) and the buffered analog output (OUT1). A variety of user selections exist for this option regarding standard 5.08 mm pitch components and mounting alternatives (top/ bottom). 3. Using 20 pin connector strips or an IDC connector, most of the system information can be reached. 4-2 Host integration considerations and EMI shielding If an IDC connector is being used to connect the K30 Module to a host PCB, this connector can in some situations be used as the only fixture. If the K30 PCB is instead fixed using mechanical poles and screws, no more than 2 positions should be considered. This is because the PCB should not be exposed to any mechanical stress. K30 is small and lightweight enough for 2 attachment points to be sufficient. To provide for attachments, there are 4 possible screw holes available, all of them having a collar that is electrically connected to ground (G0). These connections are, however, not totally equivalent: The two screw points in the upper left corner (having the IDC and edge connectors faced downwards, as in Figure 1) are connected to the analog ground. They are the preferred choice for connection to some EMI shield (if required). This is normally necessary only if the application is such that large EMFs are foreseen. If this option is being used, precaution must be taken so as to exclude any power supply currents. Sensor reading instability is an indication of the need for shielding or of improper enclosure system groundings. The two screw points in the right bottom corner are connected to the digital ground. Connection to some EMI housing shield is less effective when this option is used, but on the other hand the sensor may Revised 05/08 7

8 be powered via these connections. NOTE 1: To avoid ground loops, one should avoid connecting the analogue and digital grounds externally. They are connected internally on the K30 PCB. NOTE 2: The terminals are not protected against reverse voltages and current spikes! Proper ESD protection is required during handling, as well as by the host interface design. 5. Maintenance The K30 Module is basically maintenance free in normal environments thanks to the built-in selfcorrecting ABC algorithm. Discuss your application with Figaro in order to get advice for a proper calibration strategy. When checking sensor accuracy, please note that sensor accuracy is defined at continuous operation, at least 3 weeks after installation. 6. WARRANTY and Limitation of Liability 6-1 Warranty The manufacturer warrants that for a period of twenty four (24) months following receipt by Buyer the Product supplied by Figaro to Buyer will be, under normal use and care, free from defects in workmanship or material and to be in material conformity with manufacturer's specifications. Units returned to Figaro for warranty repairs shall be shipped to Figaro at Buyer s expense, according to Figaro's instruction. Within ninety (90) days of the receipt of product, Figaro shall replace or repair such units and shall ship them to Buyer s designated return destination, freight prepaid. 6-2 Warranty limitations This warranty does not extend to any unit that has been subject to misuse, neglect or accident; that has been damaged by causes external to the unit; that has been used in violation of Figaro's instructions; that has been affixed to any non-standard Accessory attachment; or that has been modified, disassembled, or reassembled by anyone other than Figaro. 6-3 Limitation of liability The retailer is not responsible for any consequential loss or damages, which may occur by reason of purchase and use of this product. The warranty is, in any event, strictly limited to the replacement/repair of the product Figaro USA Inc. 121 S. Wilke Rd. Suite 300 Arlington Heights, IL USA Tel.: (1) Fax.: (1) figarousa@figarosensor.com Revised 05/08 8