MQ-7B MQ-7 Carbon Monoxide Gas Sensor for Industrial Applications
1. Applications:
- Residential CO Safety Monitoring: Widely used in home CO detectors to monitor carbon monoxide leaks from gas stoves, water heaters, fireplaces, or faulty heating systems, protecting families from CO poisoning.
- Portable Personal Protection: Integrated into small, portable gas detectors for personal use—such as by maintenance workers, gas station staff, or indoor air quality inspectors—to detect CO in real time during on-site operations.
- Industrial Low-Concentration Detection: Applied in light industrial scenarios (e.g., small workshops, storage rooms with fuel-burning equipment) to monitor low CO concentrations (typically 20–1000 ppm) and trigger early warnings for minor leaks.
- Automotive Auxiliary Detection: Used in some vehicle-related systems (e.g., garage air quality monitors) to detect CO buildup from idling cars, preventing risks in enclosed or semi-enclosed parking spaces.
2. Features:
- Cost-Effective & Easy to Use: Low manufacturing cost compared to high-end industrial sensors; simple pin configuration (power, ground, signal) allows easy integration into Arduino, Raspberry Pi, or basic electronic circuits.
- Targeted Sensitivity to CO: Optimized for detecting carbon monoxide, with high sensitivity to low CO concentrations (20–1000 ppm, adjustable for higher ranges); minimal response to common interfering gases like methane or propane (with proper calibration).
- Wide Operating Voltage Range: Typically works with 5V DC power supply, compatible with most low-voltage electronic platforms, making it suitable for DIY projects or consumer electronics.
- Rapid Warm-Up & Response: Requires a short warm-up time (usually 2–5 minutes) to stabilize; T90 response time is generally < 10 seconds for CO concentration changes, enabling quick risk alerts.
- Compact & Lightweight Design: Small size (often Φ20mm × 18mm) and low weight, easy to install in compact devices like handheld detectors or wall-mounted home alarms.
- Cost-Effective Maintenance: No need for frequent replacement of consumables; supports periodic calibration (via simple circuit adjustments) to maintain measurement accuracy over time.
|
Parameter
|
Symbol
|
Value
|
Remarks
|
| Circuit Voltage |
VC |
5 V ± 0.1 V (AC or DC) |
|
| Heating Voltage (High) |
VH(H) |
5 V ± 0.1 V (AC or DC) |
|
| Heating Voltage (Low) |
VH(L) |
1.4 V ± 0.1 V (AC or DC) |
|
| Load Resistance |
RL |
Adjustable |
|
| Heating Resistance |
RH |
33 Ω ± 5% (at room temperature) |
|
| Heating Time (High) |
TH(H) |
60 ± 1 s |
|
| Heating Time (Low) |
TH(L) |
90 ± 1 s |
|
| Heating Consumption |
PH |
About 350 mW |
|
| Operating Temperature Range |
Tao |
-20 °C - 50 °C |
|
| Storage Temperature Range |
Tas |
-20 °C - 50 °C |
It is recommended to store at 0 °C - 20 °C |
| Operating Humidity Range |
RH |
< 95% rh |
Non - condensing |
| Oxygen Concentration |
O2 |
21% (standard condition) |
The minimum value is over 2%, and oxygen concentration can affect sensitivity |
| Detecting Range |
|
20 ppm - 2000 ppm (Carbon Monoxide) |
Some sources also mention 10 - 10000 ppm |
| Sensitive Resistance |
RS |
2 k - 20 k (in 100 ppm CO) |
|
| Sensitivity |
|
≥3% |
|
| Response Time |
|
≤1 s |
|
| Recovery Time |
|
≤30 s |
|
| Size |
|
35x20x11 mm (or other dimensions in different sources) |
|
