Methane; [Calibrated]; Specifications - Libelium Smart Cities PRO Technical Manual

5.16. Methane

[Calibrated]

5.16.1. Specifications

Main gas: Methane CH
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
Chlorine
Hydrogen Sulfide
HMDS
Figure: Inhibition and poisoning effects
Sockets for Waspmote OEM:
SOCKET_1
•
Sockets for Plug & Sense!:
SOCKET_B
•
SOCKET_C
•
SOCKET_F
•
Average consumption: 68 mA
Note: The Methane (CH
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.
(CH )
4
4
12hrs 20ppm Cl
12hrs 40ppm H
) and Combustible Gas Sensor and the CO2 Sensor have high power requirements and
4
and Combustible
Conditions
, 50 % sensitivity loss, 2 day
2
recovery
S, 50 % sensitivity loss, 2 day
2
recovery
9 hrs @ 10ppm HMDS
-66-
Gas Sensor
Figure: Image of the Methane (CH
Combustible Gas Sensor (pellistor) mou-
nted on its AFE module
Effect
< 10% loss
< 50% loss
50% activity loss
Sensors
) and
4
v7.3