S8-0053

Overview

Product Specification

SenseAir ® S8 LP

Miniature infrared CO 2 sensor module

Target gas CO 2

Operating Principle Non-dispersive infrared (NDIR)

Measurement range 400 to 2000 ppm (Note 1). 0 to 10000 ppm extended range (Note 2)

Measurement interval 4 seconds

Accuracy ±40ppm ±3% of reading (Notes 3 and 4)

Pressure dependence + 1.6 % reading per kPa deviation from normal pressure

Response time 2 minutes by 90%

Operating temperature 0 to 50° C

Operating humidity 0 to 85% RH non condensed

Storage temperature -40 to +70 C

Dimensions 33.5 x 20 x 8.5 mm (max dimensions)

Weight < 8 grams

Power supply 4.5 V to 5.25 V unprotected against surges and reverse connection

Power consumption 300 mA peak, < 18 mA average.

Life expectancy 15+ years

Compliance with Emission: EN 61000-6-3:2007, EN 61000-6-4:2007 Immunity: EN 61000-6-1:2007 RoHS directive 2011/65/EU

Serial communication UART, Modbus protocol (Note 5). Direction control pin for direct connection to RS485 receiver integrated circuit.

Alarm output, Open Collector 1000/800 ppm Normal state is conducting max 100 mA. Transistor open at CO 2 High, OR Power Low, OR at Sensor Failure

Alarm state open

PWM output, 1 kHz 0 to 100% duty cycle for 0 to 2000 ppm 3.3V push-pull CMOS output, unprotected

Maintenance Maintenance-free for normal indoor applications with SenseAir ® ABC on.

Table 1. Key technical specification for the SenseAir ® S8 LP __________________________________________________________________

Note 1: Sensor is designed to measure in the range 400 to 2000 ppm with specified in the table accuracy. Nevertheless exposure to concentrations below 400 ppm may result in incorrect operation of ABC algorithm and shall be avoided for model with ABC on.

Note 2: Sensor provides readings via UART in the extended range but the accuracy is degraded compared to specification in the table one.

Note 3: In normal IAQ applications. Accuracy is defined after minimum 3 weeks of continuous operation with ABC. However, some industrial applications do require maintenance. Please, contact SenseAir for further information!

Maximum voltage on Alarm_OC - 0.3 12 V 1,3

Table 2. Absolute maximum ratings specification for the SenseAir ® S8 LP ___________________________________________________________________ Note 1: Specified parameter relies on specification of subcontractor and is not tested by SenseAir

Note 2: Refer chapter “Terminal Description” for rated voltage information

Note 3: Alarm_OC pin is internally pulled up to G+. External pull up to higher voltage will provide resistive divider powering sensor via high resistance.

Diffusion area

Figure 2. Diffusion area

DVCC_out UART_RxD

Alarm_OC

UART_TxD UART_R/T bCAL_in

PWM 1kHz

Pin Function

Power pins

G0 Power supply minus terminal Sensor’s reference (ground) terminal

G+ referred to G0 Power supply plus terminal Operating voltage range

Unprotected against reverse connection! 4.5 V to 5.25 V

Series resistance No internal protection!

Nominal voltage 3.3 VDC

Allowed source current 6 mA max

Voltage precision (Note 1) ± 0.75% is typical, ± 3% is max

Communication pins

Absolute max voltage range (Note 1) G0 - 0.3V to DVCC_out + 0.5V

Internal pull up to DVCC_out resistor 120k

Output low level (Note 1) 0.75 VDC max at 10mA sink

Output high level (Note 1) 2.4 VDC at 2mA source

Absolute max voltage range(Note 1) G0 - 0.3V to DVCC_out + 0.5V

Input low level (Note 1) - 0.3V to 0.75V

Input high level (Note 1) 2.3V to DVCC_out + 0.3V

Input / output

bCAL_in/ CAL Digital input forcing background calibration. Configured as digital input (when closed for minimum 4, max 8 seconds) bCAL (background calibration) assuming 400 ppm CO2 sensor exposure Zero calibration (when closed for minimum 16 seconds) CAL (zero calibration) assuming 0 ppm CO2 sensor exposure

No internal protection, Pulled up to DVCC_out at processor reset (power up and power down)

PWM 1 kHz PWM output Configured as digital output Used for direct reading by customer’s microcontroller or to provide analog output. Refer “Use scenario suggestion” for details and ideas

Duty cycle min 0%, output Low

Duty cycle max 100%, output High

PWM resolution 0.5us ± 4%

PWM period 1ms ± 4%

Internal pull down do G0 resistor 120k

No internal protection, Pulled up to G+ at processor reset (power up and power down)

Absolute max voltage range(Note 1) G0 - 0.3V to 5.5V

Internal pull up to G+ resistor 120k

Max sink current (Note 1) 100 mA

Saturation voltage (Note 1) 2.3V to DVCC_out+0.3V

Warning! ESD

sensitive device!

Applications

ABC parameter Specification

ABC period 8 days

Input Default function

bCAL_in (when closed for minimum 4, max 8 seconds) bCAL (background calibration) assuming 400 ppm CO 2 sensor exposure

CAL_in (when closed for minimum 16 seconds) CAL (zero calibration) assuming 0 ppm CO 2 sensor exposure

Table 5. Switch input default configurations for SenseAir ® S8 LP

Bit # Error code

Error description Suggested action

0 1 Fatal Error Try to restart sensor by power OFF/ON. Contact local distributor.

2 4 Algorithm Error . Indicate wrong configuration.

Try to restart sensor by power OFF/ON. Check detailed settings and configuration with software tools. Contact local distributor.

5 32 Out of Range Error Accompanies most of other errors. Can also indicate overload or failures of sensors and inputs. Resets automatically after source of error disappearance.

Try sensor in fresh air. Perform CO 2 background calibration. Check detailed status of measurements with software tools . See Note 1!

Figure 1. SenseAir ® S8 Article no. 004-0-0017

BeiJing DiHui Technology Co.Ltd

SenseAir® AB

Box 96 Stationsgatan 12 SE- 82060 Delsbo Sweden

Room 1706.Building1. BiXing Garden Luozhuangxili,Zhichun Road Haidian district,Beijing China