Sensors
Many of the sensors available for Smart Cities PRO are actually migrated from the Gases PRO sensor board, where they were integrated initially. For a better understanding of the characteristics of sensors, its calibration and performance, it is highly advised to read the Gases PRO Technical Guide, specially the chapters "Gases PRO sensor board", "Hardware" and "Sensors".

Temperature, Humidity and Pressure Sensor

The BME280 is a digital temperature, humidity and atmospheric pressure sensor developed by Bosch Sensortec.
Figure: Temperature, Humidity and Pressure Sensor

Specifications

Electrical characteristics
Supply voltage: 3.3 V Sleep current typical: 0.1 μA Sleep current maximum: 0.3 μA
Temperature sensor
Operational range: -40 ~ +85 ºC Full accuracy range: 0 ~ +65 ºC Accuracy: ±1 ºC (range 0 ºC ~ +65 ºC) Response time: 1.65 seconds (63% response from +30 to +125 °C). Typical consumption: 1 μA measuring
Humidity sensor
Measurement range: 0 ~ 100% of relative humidity (for temperatures < 0 °C and > 60 °C see figure below) Accuracy: < ±3% RH (at 25 ºC, range 20 ~ 80%) Hysteresis: ±1% RH Operating temperature: -40 ~ +85 ºC Response time (63% of step 90% to 0% or 0% to 90%): 1 second Typical consumption: 1.8 μA measuring Maximum consumption: 2.8 μA measuring
Pressure sensor
Measurement range: 30 ~ 110 kPa Operational temperature range: -40 ~ +85 ºC Full accuracy temperature range: 0 ~ +65 ºC Absolute accuracy: ±0.1 kPa (0 ~ 65 ºC) Typical consumption: 2.8 μA measuring Maximum consumption: 4.2 μA measuring

Measurement process

The BME280 is as combined digital humidity, pressure and temperature sensor based on proven sensing principles. The humidity sensor provides an extremely fast response time for fast context awareness applications and high overall accuracy over a wide temperature range.
The pressure sensor is an absolute barometric pressure sensor with extremely high accuracy and resolution and drastically lower noise.
The integrated temperature sensor has been optimized for lowest noise and highest resolution.
Its output is used for temperature compensation of the pressure and humidity sensors and can also be used for estimation of the ambient temperature.
When the sensor is disabled, current consumption drops to 0.1 μA.
You can find a complete example code for reading the BME280 sensor in the following link: https://development.libelium.com/scp-v30-05-temperature-humidity-and-pressure-senso/

Socket

This sensor can be connected in sockets 1, 2, 3, 4 and 5 in Waspmote OEM and sockets A, B, C, E and F in Plug & Sense!.
Figure: Temperature, Humidity and Pressure Sensors in sockets 1, 2, 3, 4 and 5
In the image above we can see highlighted the four pins of the terminal block where the sensor must be connected to the board. The white dot on the BME280 must match the white mark on the Smart Cities PRO Sensor Board. Please mind that each socket has 3 rows, but only 2 are used for that sensor, because it only has 2x2 pins. A bad connection can cause malfunction or even hardware damage.

Ultrasound sensors

Specifications

Figure: Ultrasonic I2CXL-MaxSonar®-MB7040 from MaxBotix™ Sensor
I2CXL-MaxSonar®-MB7040™
Operation frequency: 42 kHz Maximum detection distance: 765 cm Interface: Digital bu Power supply: 3.3 V Consumption (average): 2.1 mA Consumption (peak): 50 mA Usage: Indoors and outdoors (IP-67)
Figure: Ultrasonic I2CXL-MaxSonar®-MB7040 sensor dimensions
In the figure below we can see a diagram of the detection range of the sensor developed using different detection patterns (a 0.63 cm diameter dowel for diagram A, a 2.54 cm diameter dowel for diagram B, an 8.25cm diameter rod for diagram C and a 28 cm wide board for diagram D):
Figure: Diagram of the sensor beam extracted from the data sheet of the XL-MaxSonar®-WRA1TM sensor from MaxBotix
I2CXL-MaxSonar®-MB1202™
Figure: Ultrasonic I2CXL-MaxSonar®- MB1202 from MaxBotix™ Sensor
Operation frequency: 42 kHz Maximum detection distance: 765 cm Consumption (average): 2 mA Consumption (peak): 50 mA Usage: Indoors only
Figure: Ultrasonic I2CXL-MaxSonar®-MB1202 Sensor dimensions
In the figure below we can see a diagram of the detection range of the sensor developed using different detection patterns (a 0.63 cm diameter dowel for diagram A, a 2.54 cm diameter dowel for diagram B, an 8.25 cm diameter rod for diagram C and a 28 cm wide board for diagram D):
Figure: Diagram of the sensor beam extracted from the data sheet of the Ultrasonic I2CXL-MaxSonar®-MB1202 sensor from MaxBotix

Measurement Process

The MaxSonar® sensors from MaxBotix can be connected through the digital bus interface.
In the next figure, we can see a drawing of two example applications for the ultrasonic sensors, such as liquid level monitoring or presence detection.
Figure: Examples of application for the MaxSonar® sensors
The MB7040 sensor is endowed with an IP-67 casing, so it can be used in outdoors applications, such as liquid level monitoring in storage tanks.
You can find a complete example code for reading the distance in the following link: https://development.libelium.com/scp-v30-06-ultrasound-sensor/

Socket

These sensors can be connected in socket 1, 2, 3, 4 and 5 in Waspmote OEM and sockets A, B, C, E and F in Plug & Sense!.
Figure: Images of the sockets for connecting the MaxSonar® Sensors

Luminosity (Luxes accuracy) Sensor

Figure: Image of the Luminosity Sensor

Specifications

Electrical characteristics Dynamic range: 0.1 to 40000 lux Spectral range: 300 ~ 1100 nm Voltage range: 2.7 ~ 3.6 V Supply current typical: 0.24 mA Sleep current maximum: 0.3 μA Operating temperature: -30 ~ 70 ºC

Measurement process

This is a light-to-digital converter that transforms light intensity into a digital signal output. This device combines one broadband photo-diode (visible plus infrared) and one infrared-responding photo-diode on a single CMOS integrated circuit capable of providing a near-photopic response over an effective 20-bit dynamic range (16-bit resolution). Two integrating ADCs convert the photo-diode currents to a digital output that represents the irradiance measured on each channel. This digital output in lux is derived using an empirical formula to approximate the human eye response.
You can find a complete example code for reading the luminosity in the following link: https://development.libelium.com/scp-v30-07-luxes-sensor/

Socket

This sensor can be connected in socket 1, 2, 3, 4 and 5 in Waspmote OEM and sockets A, B, C, E and F in Plug & Sense!
Figure: Luxes sensors connected in sockets 1, 2, 3, 4 and 5
In the image above we can see highlighted the four pins of the terminal block where the sensor must be connected to the board. The white dot on the luxes board, must match the mark of the Smart Cities PRO Sensor Board. Please mind that each socket has 3 rows, but only 2 are used for that sensor, because it only has 2x2 pins. A bad connection can cause malfunction or even hardware damage.

Particle Matter (PM1 / PM2.5 / PM10) - Dust Sensor

Since February 2019, the OPC-N3 sensor is supplied instead of the OPC-N2. The OPC-N3 has taken the success of the older OPC-N2 unit and has improved it further. With the same dimensions and power/ interface as the N2, the OPC-N3 now measures from 0.35 μm to 40 μm, sorting into 24 size bins. Features include improved aerodynamics with reduction of particle deposition, better low end performance, extended upper size measurements and high/low flow rate digital selection. The OPC-N3 can measure from clean rooms to pollution levels to 2,000 μg/m3 with the unique feature of being able to size classify pollen.
Figure: Image of the Particle Matter sensor, encapsulated

Specifications

Sensor: OPC-N3
Performance characteristics Laser classification: Class 1 as enclosed housing Particle range (μm): 0.35 to 40 spherical equivalent size (based on RI of 1.5, S of 1.65) Size categorization (standard): 24 software bins Sampling interval (seconds): 1 to 30 histogram period Total flow rate: 5.5 L/min Sample flow rate: 280 mL/min Max particle count rate: 10000 particles/second Max coincidence probability: 0.84% at 10,000,000 particles/L, 0.24% at 500 particles/L
Power characteristics Measurement mode (laser and fan on): 270 mA @ 5 V (typical) Voltage range: 4.8 to 5.2 V DC
Enclosure Waterproof Dimensions: 122 x 82 x 85 mm (without fixing lugs) Material: Polycarbonate Cable length: 0.6 m
Operation conditions Temperature range: -10 ºC to 50 ºC Operating humidity: 0 to 99% RH non-condensing
This sensor has a high current consumption. It is very important to turn on the sensor to perform a measure and then, turn it off to save battery. Also, it is advised to operate with a minimum battery level of 40%, just to avoid voltage drops (due to high current peaks) which could lead to resets in the system.
Dust, dirt or pollen may be accumulated inside the dust sensor structure, especially when the sensor is close to possible solid particle sources: parks, construction works, deserts. That is why it is highly recommended to perform maintenance/cleaning tasks in order to have accurate measures. This maintenance/cleaning frequency may vary depending on the environment conditions or amount of obstructing dust. In clean atmospheres or with low particle concentrations, the maintenance/cleaning period will be longer than a place with a high particle concentrations.
Do not handle the sticker seals of the enclosure (Warranty stickers). Their integrity is the proof that the sensor enclosure has not been opened. If they have been handled, damaged or broken, the warranty is automatically void.
DO NOT remove the external housing: this not only ensures the required airflow, also protects the user from the laser light. Removal of the casing may expose the user to Class 3B laser radiation. You must avoid exposure to the laser beam. Do not use if the outer casing is damaged. Return to Libelium. Removal of the external housing exposes the OPC circuitry which contains components that are sensitive to static discharge damage.
The Particle Matter (PM1 / PM2.5 / PM10) -- Dust Sensor is available only for the Plug & Sense! line (socket D).

Particle matter: the parameter

Particle matter is composed of small solid or liquid particles floating in the air. The origin of these particles can be the industrial activity, exhaust fumes from diesel motors, building heating, pollen, etc. This tiny particles enter our bodies when we breath. High concentrations of particle matter can be harmful for humans or animals, leading to respiratory and coronary diseases, and even lung cancer. That is why this is a key parameter for the Air Quality Index.
Some examples:
  • Cat allergens: 0.1-5 μm
  • Pollen: 10-100 μm
  • Germs: 0.5-10 μm
  • Oil smoke: 1-10 μm
  • Cement dust: 5-100 μm
  • Tobacco smoke: 0.01-1 μm
The smaller the particles are, the more dangerous, because they can penetrate more in our lungs. Many times, particles are classified:
  • PM1: Mass (in μg) of all particles smaller than 1 μm, in 1 m3
  • PM2.5: Mass (in μg) of all particles smaller than 2.5 μm, in 1 m3
  • PM10: Mass (in μg) of all particles smaller than 10 μm, in 1 m3
Many countries and health organizations have studied the effect of the particle matter in humans, and they have set maximum thresholds. As a reference, the maximum allowed concentrations are about 20 μm/m3 for PM2.5 and about 50 μm/m3 for PM10.
High humidity or foggy environments could affect the measures of the sensor. The particles can be swollen by or coated by water. This results in measures higher than in dry environments.
If high humidity, fog or mist are present, then the OPC will actually measure the water droplets in the air, causing very high readings.

Measurement process

Like conventional optical particle counters, the OPC-N3 measures the light scattered by individual particles carried in a sample air stream through a laser beam. These measurements are used to determine the particle size (related to the intensity of light scattered via a calibration based on Mie scattering theory) and particle number concentration. Particle mass loading- PM2.5 or PM10, are then calculated from the particle size spectra and concentration data, assuming density and refractive index. To generate the air stream, the OPC-N3 uses only a miniature low-power fan.
The OPC-N3 classifies each particle size, at rates up to ~10,000 particles per second, adding the particle diameter to one of 24 "bins" covering the size range from ~0.35 to 40 μm. The resulting particle size histograms can be evaluated over user-defined sampling times from 1 to 30 seconds duration, the histogram data being transmitted along with other diagnostic and environmental data (air temperature and air humidity). When the histogram is read, the variables in the library are updated automatically. See the API section to know how to manage and read this sensor.
You can find a complete example code for reading the Particle Matter Sensor in the following link: https://development.libelium.com/scp-v30-04-particle-matter-sensor/

Noise / Sound Level Sensor

Specifications of the Sound Level Sensor probe

  • Target parameter: LeqA
  • Microphone sensitivity: 12.7 mV/Pa
  • Range of the sensor: 50 dBA to 100 dBA
  • Accuracy: ±0.5 dBA (1 kHz)
  • Frequency range: 20 Hz -- 20 kHz
  • Omni-directional microphone
  • A-weighting measure
  • Sound pressure level measurement (no weighting filter)
  • FAST mode (125 ms) and SLOW mode (1 second), software configurable

Specifications of the enclosure

  • Dimensions: 124 x 122 x 55 mm
  • Material: polycarbonate
  • Sealing: polyurethane
  • Cover screws: stainless steel
  • Ingress protection: IP65
  • Impact resistance: IK08
  • Rated insulation voltage AC: 690 V
  • Rated insulation voltage DC: 1000 V
  • Heavy metals-free
  • Weatherproof: true - nach UL 746 C
  • Ambient temperature (min.): -10 °C
  • Ambient temperature (max.): 50 °C
  • Approximated weight: 400 g
  • Data cable length: 0.6 m (cable from Noise Level Sensor to Plug & Sense!)

Sound pressure level measurement

The sound pressure level or acoustic pressure level is a measure of the effective pressure of a sound relative to a reference value, normally referenced to pressure in air (20 µPa), which is considered as the threshold of the human hearing. The expression of the sound pressure level is defined by:
Figure: Sound pressure level expressiony
Where p is the root mean square sound pressure and p~0~ is the reference sound pressure (20 µPa). The next table shows some examples of different sound pressure measurements:

Equivalent continuous sound level

The sound pressure level parameter, explained in the previous section, is not much used in noise measurements. Instead, an average value called Leq, is used. Equivalent Continuous Sound Level (Leq) is the average of the sound pressure level during a period of time. This value is very used when the noise level is varying quickly. Below the equation to calculate the Leq value in decibels.
The Leq is the most used parameter by most countries for measuring the exposure to noise levels and earing damage risk. A better approximation to the human ear response is the LAeq (equivalent continuous A-weighted sound pressure level). The A-weighting filter is described in the next section of this guide.

The A-weighting

The A-weighting is the most used curve of the family of curves defined by the IEC 61672 standard. It is very used for measuring environmental and industrial noise, due to the fact that the curve follows the frequency sensitivity of the human ear. Noise measurements made with the A-weighting scale are designated dBA. The A-weighting also predicts quite well the damage risk of the ear. The next graph shows the response of the A-weighting across the frequency range 10 Hz -- 20 kHz.
Figure: Graph of the A-weighting curve

International standard IEC 61672-1:2013

The new Noise / Sound Level Sensor has been designed following the specifications of the IEC 61672 standard for sound meters. Specifically with an accuracy of ±2 dBA similar to the Class 2 type devices. The value given is the LeqA (Equivalent continuous sound level, with A weighting) that allows to calculate the average sound pressure level during a period of time. Leq is often described as the average noise level during a noise measurement and it is the magnitude used for many regulations of noise control at work places and the street.

Measurement process

As mentioned previously, the Sound Level Sensor can only be used in combination with a Plug & Sense! Smart Cities PRO device. Once the sensor is connected following the previous steps, the Waspmote Plug & Sense! unit must be programmed for reading the sound pressure values.
You can find a complete example code for reading the temperature sensor in the following link: https://development.libelium.com/scp-v30-08-noise-level/

Calibration Tests

In order to ensure the high quality of the Noise / Sound Level Sensor, each device is verified in an independent test laboratory.
Tests are performed inside an isolated anechoic chamber. The sound sensor probes are exposed to 5 different levels of white noise, created by a specialized sound generator and a cutting-edge, omni-directional speaker: 55, 65, 75, 85 and 95 dBA. The exact level is confirmed by the technician with a certified IEC 61672 soundmeter, placed at the same distance from the sound source than the 16 sensors. For each noise level, the output of each one of the 16 sensors is captured by a software system.
After those tests, an official test report is issued by the laboratory for every Noise / Sound Level Sensor, so the customer can verify the accuracy in dBA at different frequencies for each sound level probe. See below an example of this document.
Libelium ships every Noise / Sound Level Sensor with its test report. It takes some weeks to the laboratory to issue the test reports, so a Noise / Sound Level Sensor may be sent without the test report; in this case, the customer can to ask for the test report to their Sales agent.
Figure: Example of test report obtained in the laboratory
Figure: Example of test report obtained in the laboratory

Mounting the Noise / Sound Level Sensor and supplying power

The Noise Level Sensor has been designed to be used with the Waspmote Plug & Sense! Smart Cities PRO and it cannot be used independently. This sensor cannot be used on a Waspmote OEM with a Smart Cities PRO board, for example.
The Sound Level Sensor consists of the next items shown in the figure below:
Figure: Noise Level Sensor items: 1 Noise Level Sensor. 2 Noise Level Sensor enclosure. 3 Data cable. 4 Power supply cable. 5 Protection cover
The images below show the different sockets of the Noise Level Sensor.
Figure: Identification of the connectors
Figure: Power supply connector
Figure: Noise Level Sensor probe
To connect the Sound Level Sensor probe to the enclosure, It should be taken into account that the sensor probe connector has only one matching position. The user should align the sensor probe connector looking at the little notch of the connector (see image below). Notice that the sensor connector is male-type and the enclosure sensor connector is female-type.
Figure: Detail of the sensor probe connector
Besides, there is a locking nut which should be screwed till the connector is completely fixed to the enclosure.
Figure: Connecting the sensor probe to the enclosure
After connecting the sensor, connect the the power supply cable to the USB connector, as shown in the picture below and the Noise Level Sensor will power up. Then, connect one end of data cable to the Sound Level Sensor and the other one to the associated Plug & Sense! Smart Cities PRO device.
Figure: Connecting the data cable and the power supply cable to the Noise Level Sensor
Figure: Connecting the data cable to the associated Plug & Sense! Smart Cities device
Finally, the Noise Level Sensor can be installed outdoors in a streetlight or directly on a wall. The protection cover should be placed like the pictures below, to protect the Sound Level Sensor probe from the rain.
Figure: Installing the Noise Level Sensor on a wall
Notice that the power supply cable has a waterproof end, suitable for outdoor applications. But, on the other side, it has a non-waterproof end thought to be connected to a USB charger (AC/DC, 5 V /2.5A output). Bear in mind that this end is not waterproof so it cannot be used outdoors. Please protect it accordingly.
A typical application is to power a node placed on the facade of a building; the power supply cables go indoors through a nearby window and the USB ends remain indoors, connected to a wall adapter. Many lampposts also have a 220 V output inside.
Figure: Typical installation of the Noise Level Sensor

Carbon Monoxide (CO) Gas Sensor for low concentrations [Calibrated]

Figure: Image of the Carbon Monoxide Sensor for low concentrations mounted on its AFE module

Specifications

Gas: CO Sensor: CO-A4
Performance Characteristics Nominal Range: 0 to 25 ppm Maximum Overload: 2000 ppm Long Term Sensitivity Drift: < 10% change/year in lab air, monthly test Long Term zero Drift: < ±100 ppb equivalent change/year in lab air Response Time (T90): ≤ 20 seconds Sensitivity: 220 to 375 nA/ppm Accuracy: as good as ±0.1 ppm* (ideal conditions) H2S filter capacity: 250000 ppm·hrs
Operation Conditions Temperature Range: -30 ºC to 50 ºC Operating Humidity: 15 to 90% RH non-condensing Pressure Range: 80 to 120 kPa Storage Temperature: 0 ºC to 20 ºC Expected Operating Life: 3 years in air
Sockets for Waspmote OEM:
  • SOCKET_1
  • SOCKET_3
  • SOCKET_5
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: less than 1 mA
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
The electrochemical sensors must be always powered on in order to get optimum measurements. This implies a power consumption, however it improves the performance of the sensor. This should also be applied when entering sleep modes so the sensor is not powered off selecting the proper sleep option.
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.

Cross-sensitivity data

Gas
Formula
Concentration (ppm)
Output Signal (ppm CO equivalent)
Hydrogen Sulfide
H2S
5
< 0.1
Sulfur Dioxide
SO2
5
< -2
Cholrine
Cl2
5
< 0.1
Nitric Oxide
O2
5
< -2
Sulfur Dioxide
NO2
5
< 0.1
Hydrogen
H2
100
< 10
Ethylene
C2H4
100
< 0.5
Ammonia
NH 3
20
< 0.1
Figure: Cross-sensitivity data for the CO Sensor for low concentrations
You can find a complete example code for reading the CO Sensor for low concentrations in the following link: https://development.libelium.com/scp-v30-01-electrochemical-gas-sensors/

Carbon Dioxide (CO2) Gas Sensor [Calibrated]

Specifications

Figure: Image of the Carbon Dioxide Sensor mounted on its AFE module
Gas: CO2 Sensor: INE20-CO2P-NCVSP
Performance Characteristics Nominal Range: 0 to 5000 ppm Long Term Output Drift: < ± 250 ppm/year Warm up time: 60 seconds @ 25 ºC At least 30 min for full specification @ 25 °C Response Time (T90): ≤ 60 seconds Resolution: 25 ppm Accuracy: as good as ±50 ppm*, from 0 to 2500 ppm range (ideal conditions) as good as ±200 ppm*, from 2500 to 5000 ppm range (ideal conditions)
Operation Conditions Temperature Range: -40 ºC to 60 ºC Operating Humidity: 0 to 95% RH non-condensing Storage Temperature: -40 ºC to 85 ºC MTBF: ≥ 5 years
Sockets for Waspmote OEM:
  • SOCKET_1
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: 80 mA
The CO2 Sensor and the Methane (CH4) and Combustible Gas Sensor have high power requirements and cannot work together in the same Smart Cities PRO Sensor Board. The user must choose one or the other, but not both.
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.
You can find a complete example code for reading the CO2 Sensor in the following link: https://development.libelium.com/scp-v30-02-ndir-gas-sensors/

Molecular Oxygen (O2) Gas Sensor [Calibrated]

Figure: Image of the Molecular Oxygen Sensor mounted on its AFE module

Specifications

Gas: O2 Sensor: LFO2-A4
Performance Characteristics Long Term Output Drift: < 1% signal/3 months Response Time (T90): ≤ 17 seconds Sensitivity: 80-130 μA @ 20.9% O2 Accuracy: as good as ±0.1% (ideal conditions)
Operation Conditions Temperature Range: -30 ºC to 50 ºC Operating Humidity: 5 to 95% RH non-condensing Pressure Range: 80 to 120 kPa Storage Temperature: 3 ºC to 20 ºC, 6 months Expected Operating Life: 2 years until 85% original output of 20.9% O2
Note: Previously, Libelium offered the equivalent O2 sensor 4-OL, by Eurogas.
Sockets for Waspmote OEM:
  • SOCKET_1
  • SOCKET_3
  • SOCKET_5
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: less than 1 mA
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
The electrochemical sensors must be always powered on in order to get optimum measurements. This implies a power consumption, however it improves the performance of the sensor. This should also be applied when entering sleep modes so the sensor is not powered off selecting the proper sleep option.
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.
You can find a complete example code for reading the O2 Sensor in the following link: https://development.libelium.com/scp-v30-01-electrochemical-gas-sensors/

Ozone (O3) Gas Sensor [Calibrated]

Figure: Image of the Ozone Sensor mounted on its AFE module

Specifications

Gas: O3 Sensor: OX-A431
Performance Characteristics Nominal Range: 0 to 18 ppm Maximum Overload: 50 ppm Long Term sensitivity Drift: -20 to -40% change/year Response Time (T90): ≤ 45 seconds Sensitivity: -200 to -550 nA/ppm Accuracy: as good as ±0.2 ppm* (ideal conditions) High cross-sensitivity with NO2 gas. Correction could be necessary in ambients with NO2.
Operation Conditions Temperature Range: -30 ºC to 40 ºC Operating Humidity: 15 to 85% RH non-condensing Pressure Range: 80 to 120 kPa Storage Temperature: 3 ºC to 20 ºC Expected Operating Life: > 24 months in air
Sockets for Waspmote OEM:
  • SOCKET_1
  • SOCKET_3
  • SOCKET_5
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: less than 1 mA
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
The electrochemical sensors must be always powered on in order to get optimum measurements. This implies a power consumption, however it improves the performance of the sensor. This should also be applied when entering sleep modes so the sensor is not powered off selecting the proper sleep option.
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.

Cross-sensitivity data

Gas
Formula
Concentration (ppm)
Output Signal (ppm CO equivalent)
Hydrogen Sulfide
H2S
5
< 10
Nitric Dioxide
NO2
5
70 to 120
Chlorine
Cl2
5
< 30
Nitric Oxide
O2
5
< 3
Sulfur Dioxide
SO2
5
< -6
Carbon Monoxide
CO
5
< 0.1
Hydrogen
H2
100
< 0.1
Ethylene
C2H4
100
< 0.1
Ammonia
NH3
20
< 0.1
Carbon Dioxide
CO2
50000
0.1
Halothane
Halothane
100
< 0.1
This sensor has a very high cross-sensitivity with NO2 gas. So, the output in ambients with NO2 will be a mix of O3 and NO2. A simple way to correct this effect is to subtract NO2 concentration from O3 concentration with an NO2 gas sensor. The measure from the NO2 sensor must be accurate in order to subtract the right value. See the related section in the "Board configuration and programming" chapter to use the right function.
You can find a complete example code for reading the O3 Sensor in the following link: https://development.libelium.com/scp-v30-01-electrochemical-gas-sensors/

Nitric Oxide (NO) Gas Sensor for low concentrations [Calibrated]

Figure: Image of the Nitric Oxide Sensor for low concentrations mounted on its AFE module

Specifications

Gas: NO Sensor: NO-A4
Performance Characteristics Nominal Range: 0 to 18 ppm Maximum Overload: 50 ppm Long Term Sensitivity Drift: < 20% change/year in lab air, monthly test Long Term zero Drift: 0 to 50 ppb equivalent change/year in lab air Response Time (T90): ≤ 25 seconds Sensitivity: 350 to 550 nA/ppm Accuracy: as good as ±0.2 ppm* (ideal conditions)
Operation Conditions Temperature Range: -30 ºC to 50 ºC Operating Humidity: 15 to 85% RH non-condensing Pressure Range: 80 to 120 kPa Storage Temperature: 0 ºC to 20 ºC Expected Operating Life: 2 years in air
Sockets for Waspmote OEM:
  • SOCKET_1
  • SOCKET_3
  • SOCKET_5
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: less than 1 mA
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
The electrochemical sensors must be always powered on in order to get optimum measurements. This implies a power consumption, however it improves the performance of the sensor. This should also be applied when entering sleep modes so the sensor is not powered off selecting the proper sleep option.
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.

Cross-sensitivity data

Gas
Formula
Concentration (ppm)
Output Signal (ppm NO equivalent)
Hydrogen Sulfide
H2S
15
-1.5
Sulfur Dioxide
SO2
5
0
Cholrine
Cl2
5
1.5
Carbon Monoxide
CO
300
0
You can find a complete example code for reading the NO Sensor for low concentrations in the following link: https://development.libelium.com/scp-v30-01-electrochemical-gas-sensors/

Nitric Dioxide (NO2) high accuracy Gas Sensor [Calibrated]

Specifications

Gas: NO2 Sensor: NO2-A43F
Performance Characteristics Nominal Range: 0 to 20 ppm Maximum Overload: 50 ppm Long Term Sensitivity Drift: < -20 to -40% change/year in lab air, monthly test Long Term zero Drift: < 20 ppb equivalent change/year in lab air Response Time (T90): ≤ 60 seconds Sensitivity: -175 to -450 nA/ppm Accuracy: as good as ±0.1 ppm* (ideal conditions) O3 filter capacity @ 2 ppm: > 500 ppm·hrs
Operation Conditions Temperature Range: -30 ºC to 40 ºC Operating Humidity: 15 to 85% RH non-condensing Pressure Range: 80 to 120 kPa Storage Temperature: 0 ºC to 20 ºC Expected Operating Life: 2 years in air
Sockets for Waspmote OEM:
  • SOCKET_1
  • SOCKET_3
  • SOCKET_5
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: less than 1 mA
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
The electrochemical sensors must be always powered on in order to get optimum measurements. This implies a power consumption, however it improves the performance of the sensor. This should also be applied when entering sleep modes so the sensor is not powered off selecting the proper sleep option.
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.

Cross-sensitivity data

Gas
Formula
Concentration (ppm)
Output Signal (ppm NO2 equivalent)
Hydrogen Sulfide
H2S
5
< -80
Cholrine
Cl2
5
< 75
Nitric Oxide
NO
5
< 5
Sulfur Dioxide
SO2
5
< -5
Carbon Monoxide
CO
5
< -5
Hydrogen
H2
100
< 0.1
Ethylene
C2H4
100
< 1
Ammonia
NH3
20
< 0.2
Carbon Dioxide
CO2
5% vol
0.1
Halothane
Halothane
100
nd
You can find a complete example code for reading the high accuracy NO2 Sensor in the following link: https://development.libelium.com/scp-v30-01-electrochemical-gas-sensors/

Sulfur Dioxide (SO2) high accuracy Gas Sensor [Calibrated]

Figure: Image of the high accuracy Sulfur Dioxide Sensor mounted on its AFE module

Specifications

Gas: SO2 Sensor: SO2-A4
Performance Characteristics Nominal Range: 0 to 20 ppm Maximum Overload: 100 ppm Long Term Sensitivity Drift: < ±15% change/year in lab air, monthly test Long Term zero Drift: <±20 ppb equivalent change/year in lab air Response Time (T90): ≤ 20 seconds Sensitivity: 320 to 480 nA/ppm Accuracy: as good as ±0.1 ppm* (ideal conditions)
Operation Conditions Temperature Range: -30 ºC to 50 ºC Operating Humidity: 15 to 90% RH non-condensing Pressure Range: 80 to 120 kPa Storage Temperature: 0 ºC to 20 ºC Expected Operating Life: 2 years in air
Sockets for Waspmote OEM:
  • SOCKET_1
  • SOCKET_3
  • SOCKET_5
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: less than 1 mA
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
The electrochemical sensors must be always powered on in order to get optimum measurements. This implies a power consumption, however it improves the performance of the sensor. This should also be applied when entering sleep modes so the sensor is not powered off selecting the proper sleep option.
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.

Cross-sensitivity data

Gas
Formula
Concentration (ppm)
Output Signal (ppm SO2 equivalent)
Hydrogen Sulfide
H2S
5
< 40
Chlorine
Cl2
5
< -70
Nitric Oxide
NO
5
< -160
Sulfur Dioxide
SO2
5
< 1.5
Carbon Monoxide
CO
5
< 2
Hydrogen
H2
100
< 1
Ethylene
C2H4
100
< 1
Ammonia
NH3
20
< 0.1
Carbon Dioxide
CO2
5% vol
< 0.1
You can find a complete example code for reading the high accuracy SO2 Sensor in the following link: https://development.libelium.com/scp-v30-01-electrochemical-gas-sensors/

Ammonia (NH3) Gas Sensor for low concentrations [Calibrated]

Figure: Image of the Ammonia Sensor for low concentrations mounted on its AFE module

Specifications

Gas: NH3 Sensor: 4-NH3-100
Performance Characteristics Nominal Range: 0 to 100 ppm Long Term Output Drift: < 2% signal/month Response Time (T90): ≤ 90 seconds Sensitivity: 135 ± 35 nA/ppm Accuracy: as good as ±0.5 ppm* (ideal conditions)
Operation Conditions
Temperature Range: -20 ºC to 50 ºC Operating Humidity: 15 to 90% RH non-condensing Pressure Range: 90 to 110 kPa Storage Temperature: 0 ºC to 20 ºC Expected Operating Life: ≥1 year in air
Sockets for Waspmote OEM:
  • SOCKET_1
  • SOCKET_3
  • SOCKET_5
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: less than 1 mA
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
The electrochemical sensors must be always powered on in order to get optimum measurements. This implies a power consumption, however it improves the performance of the sensor. This should also be applied when entering sleep modes so the sensor is not powered off selecting the proper sleep option.
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.

Cross-sensitivity data

Gas
Formula
Concentration (ppm)
Output Signal (ppm NH3 equivalent)
Carbon Monoxide
CO
300
0
Hydrogen Sulfide
H2S
5
1.5
Carbon Dioxide
CO2
5
-3
Hydrogen
H2
15
30
Isobutylene
35
-1
Ethanol
100
0
You can find a complete example code for reading the NH3 Sensor for low concentrations in the following link: https://development.libelium.com/scp-v30-01-electrochemical-gas-sensors/

Ammonia (NH3) Gas Sensor for high concentrations [Calibrated]

Figure: Image of the Ammonia Sensor for high concentrations mounted on its AFE module

Specifications

Gas: NH3 Sensor: 4-NH3-100
Performance Characteristics Nominal Range: 0 to 500 ppm Long Term Output Drift: < 10% per 6 months Response Time (T90): ≤ 90 seconds Sensitivity: 135 ± 35 nA/ppm Accuracy: as good as ±3 ppm* (ideal conditions)
Operation Conditions
Temperature Range: -20 ºC to 40 ºC Operating Humidity: 15 to 90% RH non-condensing Pressure Range: 90 to 110 kPa Storage Temperature: 0 ºC to 20 ºC Expected Operating Life: ≥1 year in air
Sockets for Waspmote OEM:
  • SOCKET_1
  • SOCKET_3
  • SOCKET_5
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: less than 1 mA
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
The electrochemical sensors must be always powered on in order to get optimum measurements. This implies a power consumption, however it improves the performance of the sensor. This should also be applied when entering sleep modes so the sensor is not powered off selecting the proper sleep option.
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.

Cross-sensitivity data

Gas
Formula
Concentration (ppm)
Output Signal (ppm NH3 equivalent)
Carbon Monoxide
CO
50
-1
Hydrogen Sulfide
H2S
25
1.5
Carbon Dioxide
CO2
5000
-3
Hydrogen
H2
1000
30
Isobutylene
C4H8
100
-1
Ethanol
C2H6O
1000
0
Sulphur Dioxide
SO2
5
8
Nitric Oxide
NO
35
0
Nitric Dioxide
NO2
5
-5
Chlorine
CL2
10
-5
You can find a complete example code for reading the NH3 Sensor for high concentrations in the following link: https://development.libelium.com/scp-v30-01-electrochemical-gas-sensors/

Methane (CH4) and Combustible Gases Sensor [Calibrated]

Figure: Image of the Methane (CH4) and Combustible Gases Sensor (pellistor) mounted on its AFE module

Specifications

Main gas: Methane CH4 Sensor: CH-A3
Performance Characteristics Nominal Range: 0 to 100% LEL methane Long Term Output Drift: < 2% signal/month Response Time (T90): ≤ 30 seconds Accuracy: as good as ±0.15% LEL* (ideal conditions)
Operation Conditions Temperature Range: -40 ºC to 55 ºC Expected Operating Life: 2 years in air
Inhibition/Poisoning
Gas
Formula
Conditions
Effect
Chlorine
CL2
2hrs 20ppm Cl 2 , 50 % sensitivity loss, 2 day recovery
< 10% loss
Hydrogen Sulfide
H2S
12hrs 40ppm H 2 S, 50 % sensitivity loss, 2 day recovery
< 50% loss
HMDS
9 hrs @ 10ppm HMDS
50% activity loss
Sockets for Waspmote OEM:
  • SOCKET_1
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: 68 mA
The Methane (CH4) and Combustible Gas Sensor and the CO2 Sensor have high power requirements and cannot work together in the same Smart Cities PRO Sensor Board. The user must choose one or the other, but not both.
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.

Sensitivity data

Hydrocarbon/Gas
% Sensitivity relative to Methane
% LEL Sensitivity to Methane
Hydrogen
130 to 140
160 to 175
Propane
150 to 190
350 to 450
Butane
150 to 180
420 to 500
n-Pentane
180 to 200
600 to 670
Nonane
150 to 170
800 to 950
Carbon Monoxide
42 to 44
17 to 18
Acetylene
150 to 170
300 to 340
Ethylene
150 to 170
270 to 320
Isobutylene
180 to 200
450 to 500
The exact values of combustible gases cannot be obtained directly. However, it is possible to obtain the other combustible gases values by activating the debug mode in the WaspSensorGas_Pro.h library: take the following data that will be printed by serial monitor (SENSITIVITY: mV/% LEL) and use it along with the sensitivity values of the table above to calculate them.
You can find a complete example code for reading the Methane (CH4) and Combustible Gases Sensor in the following link: https://development.libelium.com/scp-v30-03-pellistor-gas-sensors/

Molecular Hydrogen (H2) Gas Sensor [Calibrated]

Figure: Image of the Molecular Hydrogen Sensor mounted on its AFE module
This sensor was discontinued in 2019.

Specifications

Gas: H2 Sensor: 4-H2-1000
Performance Characteristics Nominal Range: 0 to 1000 ppm Maximum Overload: 2000 ppm Long Term Output Drift: < 2% signal/month Response Time (T90): ≤ 70 seconds Sensitivity: 20 ± 10 nA/ppm Accuracy: as good as ±10 ppm* (ideal conditions)
Operation Conditions Temperature Range: -20 ºC to 50 ºC Operating Humidity: 15 to 90% RH non-condensing Pressure Range: 90 to 110 kPa Storage Temperature: 0 ºC to 20 ºC Expected Operating Life: 2 years in air
Sockets for Waspmote OEM:
  • SOCKET_1
  • SOCKET_3
  • SOCKET_5
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: less than 1 mA
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
The electrochemical sensors must be always powered on in order to get optimum measurements. This implies a power consumption, however it improves the performance of the sensor. This should also be applied when entering sleep modes so the sensor is not powered off selecting the proper sleep option.
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.

Cross-sensitivity data

Gas
Formula
Concentration (ppm)
Output Signal (ppm H2 equivalent)
Hydrogen Sulfide
H2S
24
0
Cholrine
Cl2
10
0
Nitric Oxide
NO
35
10
Sulfur Dioxide
SO2
5
0
Carbon Monoxide
CO
50
200
Nitric Dioxide
NO2
5
0
Ethylene
C2H4
100
80
You can find a complete example code for reading the H2 Sensor in the following link: https://development.libelium.com/scp-v30-01-electrochemical-gas-sensors/

Hydrogen Sulfide (H2S) Gas Sensor [Calibrated]

Figure: Image of the Hydrogen Sulfide Sensor mounted on its AFE module

Specifications

Gas: H2S Sensor: 4-H2S-100
Performance Characteristics Nominal Range: 0 to 100 ppm Maximum Overload: 500 ppm Long Term Output Drift: < 2% signal/month Response Time (T90): ≤ 20 seconds Sensitivity: 800 ± 200 nA/ppm Accuracy: as good as ±0.1 ppm* (ideal conditions)
Operation Conditions Temperature Range: -20 ºC to 50 ºC Operating Humidity: 15 to 90% RH non-condensing Pressure Range: 90 to 110 kPa Storage Temperature: 0 ºC to 20 ºC Expected Operating Life: 2 years in air
Sockets for Waspmote OEM:
  • SOCKET_1
  • SOCKET_3
  • SOCKET_5
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: less than 1 mA
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
The electrochemical sensors must be always powered on in order to get optimum measurements. This implies a power consumption, however it improves the performance of the sensor. This should also be applied when entering sleep modes so the sensor is not powered off selecting the proper sleep option.
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.

Cross-sensitivity data

Gas
Formula
Concentration (ppm)
Output Signal (ppm H2S equivalent)
Ethanol
C2H6O
5000
+/- 1.5
Nitric Dioxide
NO2
5
-1
Nitric Oxide
NO
35
1
Sulfur Dioxide
SO2
5
1
Carbon Monoxide
CO
50
< 6
Hydrogen
H2
10000
25
Ethylene
C2H4
100
0
You can find a complete example code for reading the H2S Sensor in the following link: https://development.libelium.com/scp-v30-01-electrochemical-gas-sensors/

Hydrogen Chloride (HCl) Gas Sensor [Calibrated]

Figure: Image of the Hydrogen Chloride Sensor mounted on its AFE module
This sensor was discontinued in 2019.

Specifications

Gas: HCl Sensor: 4-HCl-50
Performance Characteristics Nominal Range: 0 to 50 ppm Maximum Overload: 100 ppm Long Term Output Drift: < 2% signal/month Response Time (T90): ≤ 70 seconds Sensitivity: 300 ± 100 nA/ppm Accuracy: as good as ±1 ppm* (ideal conditions)
Operation Conditions Temperature Range: -20 ºC to 50 ºC Operating Humidity: 15 to 90% RH non-condensing Pressure Range: 90 to 110 kPa Storage Temperature: 0 ºC to 20 ºC Expected Operating Life: 2 years in air
Sockets for Waspmote OEM:
  • SOCKET_1
  • SOCKET_3
  • SOCKET_5
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: less than 1 mA
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
The electrochemical sensors must be always powered on in order to get optimum measurements. This implies a power consumption, however it improves the performance of the sensor. This should also be applied when entering sleep modes so the sensor is not powered off selecting the proper sleep option.
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.

Cross-sensitivity data

Gas
Formula
Concentration (ppm)
Output Signal (ppm HCL equivalent)
Hydrogen Sulfide
H2S
25
130
Nitric Oxide
NO
20
50
Nitric Dioxide
NO2
10
1
Sulfur Dioxide
SO2
20
35
Carbon Monoxide
CO
100
0
Hydrogen
H2
2000
0
Nitrogen
N
1000000
0
You can find a complete example code for reading the HCl Sensor in the following link: https://development.libelium.com/scp-v30-01-electrochemical-gas-sensors/

Hydrogen Cyanide (HCN) Gas Sensor [Calibrated]

Figure: Image of the Hydrogen Cyanide Sensor mounted on its AFE module
This sensor was discontinued in 2019.

Specifications

Gas: HCN Sensor: 4-HCN-50
Performance Characteristics Nominal Range: 0 to 50 ppm Maximum Overload: 100 ppm Long Term Output Drift: < 2% signal/month Response Time (T90): ≤ 120 seconds Sensitivity: 100 ± 20 nA/ppm Accuracy: as good as ±0.2 ppm* (ideal conditions)
Operation Conditions Temperature Range: -20 ºC to 50 ºC Operating Humidity: 15 to 90% RH non-condensing Pressure Range: 90 to 110 kPa Storage Temperature: 0 ºC to 20 ºC Expected Operating Life: 2 years in air
Sockets for Waspmote OEM:
  • SOCKET_1
  • SOCKET_3
  • SOCKET_5
Sockets for Plug & Sense!:
  • SOCKET_B
  • SOCKET_C
  • SOCKET_F
Average consumption: less than 1 mA
Accuracy values are only given for the optimum case. See the "Calibration" chapter in the Gases PRO Technical Guide for more detail.*
The electrochemical sensors must be always powered on in order to get optimum measurements. This implies a power consumption, however it improves the performance of the sensor. This should also be applied when entering sleep modes so the sensor is not powered off selecting the proper sleep option.
Calibrated gas sensors are manufactured once the order has been placed to ensure maximum durability of the calibration feature. The manufacturing process and delivery may take from 4 to 6 weeks. The lifetime of calibrated gas sensors is 6 months working at maximum accuracy. We strongly encourage our customers to buy extra gas sensors to replace the original ones after that time to ensure maximum accuracy and performance.

Cross-sensitivity data

Gas
Formula
Concentration (ppm)
Output Signal (ppm HCN equivalent)
Nitric Dioxide
NO2
5
-3
Nitric Oxide
NO
35
-1
Sulfur Dioxide
SO2
5
1.5
Carbon Monoxide
CO
300
0
Ethylene
C2H4
100
0
Hydrogen Sulfide
H2S
15
30
You can find a complete example code for reading the HCN Sensor in the following link: https://development.libelium.com/scp-v30-01-electrochemical-gas-sensors/

Phosphine (PH3) Gas Sensor [Calibrated]

Figure: Image of the Phosphine Gas Sensor mounted on its AFE module
This sensor was discontinued in 2019.

Specifications

Gas: PH3 Sensor: 4-PH3-20
Performance Characteristics Nominal Range: 0 to 20 ppm Maximum Overload: 100 ppm Long Term Output Drift: < 2% signal/month Response Time (T90): ≤ 60 seconds Sensitivity: 1400 ± 600 nA/ppm Accuracy: as good as ±0.1 ppm* (ideal conditions)
Operation Conditions Temperature Range: -20 ºC to 50 ºC Operating Humidity: 15 to 90% RH non-condensing Pressure Range: 90 to 110 kPa Storage Temperature: 0 ºC to 20 ºC Expected Operating Life: 2 years in air
Sockets for Waspmote OEM:
  • SOCKET_1
  • SOCKET_3