Detection Modules
GMJA400-S Multi-Gas Detection Module
The base module of the Anhe series: one to six gas channels on a single board, 500+ gas options, six sensing principles.
View specs → Manufacturer · Shenzhen, China · since 2023
Detectors built for the setting, not for the shelf.
OEM detection modules for instrument makers, and complete monitoring layouts for the industries that use them. You name the gas and the site; we specify the hardware, the detection points and the alarm logic.
10+
Years of engineering experience
500+
Gases the sensor set covers
3000+
Industrial scenarios addressed
100+
Regions served
Where it gets used
Six settings written up in detail: which gases matter, where the detection points go, what the alarm should do, and the models that cover it.
01 · Grain depots
Grain Storage
Phosphine fumigation, CO2 blanketing and oxygen depletion monitored in one system that can drive the ventilation fans directly.
Read the solution →02 · Municipal wastewater plants
Wastewater & Pump Stations
Hydrogen sulphide and methane where they accumulate, with portable checks for the wells that fixed sensors cannot reach.
Read the solution →03 · Chemical plants
Chemical & Pharmaceutical Parks
Combustible, toxic and VOC channels in hazardous areas, with corrosion-resistant housings and interlocks to process equipment.
Read the solution →04 · Municipal solid waste incineration
Waste Incineration
Bunker and tipping hall monitoring that survives dust and heat, with multi-stage alarms that protect the sensors as well as the people.
Read the solution →05 · Environmental inspection
UAV & Robot Walk-Through
A payload small enough to fly and tough enough to walk, turning a fixed monitoring network into a survey tool.
Read the solution →06 · Vehicle assembly
Automotive Manufacturing
Paint, weld, engine test and battery assembly produce four different gas problems; the design uses one alarm strategy across all of them.
Read the solution →Selected modules
Four of the 8 models in the current catalogue. Full specifications are on each product page.
Detection Modules
GMJA400-S-MIN Ultra-Compact Single-Gas Sensor Module
35 × 25 mm and about 30 g, the smallest module in the Anhe series. Sized for handheld and wearable terminals.
View specs →
Robotic & Mobile Payloads
GMJA400-S-MOB Gas Detection Module for Quadruped Robots
A pumped payload for quadruped robots: up to four gases plus temperature and humidity, IP66, 113 × 113 × 46 mm, about 500 g.
View specs →
Energy Storage Safety
GM-TC05 Energy Storage Composite Fire Detector
Five parameters in one detector for lithium battery energy storage: hydrogen, carbon monoxide, VOC, smoke and temperature.
View specs →Delivered, not proposed
Three of the ten project references. Client names are withheld on most of them, at the client's request.
Wastewater treatment
Odour patrol at a municipal wastewater plant
A handheld odour monitor used for boundary and process-area patrols at a municipal plant, replacing spot checks with a logged walking survey.
GMJA1000 · Read the case →Pharmaceutical
Ozone monitoring in pharmaceutical production
Fixed ozone detection in a sterile production area, where ozone is used for disinfection between batches and the residual has to clear before staff return.
GM700 series · Read the case →Semiconductor
Formic acid trace leak in a semiconductor cleanroom
Trace-level detection of formic acid vapour in a wafer fab, where the acceptable concentration is far below the smell threshold.
GM700 series · Read the case →What integrators ask about first
The four things that decide whether a module is usable on a production line, answered without a sales call.
Calibrated before it ships
Every module leaves the factory with a calibration certificate covering its full measuring range. No second calibration rig on your line, no firmware work to convert raw counts into engineering units.
500+ gases, six principles
Electrochemical, catalytic bead, NDIR, PID, thermal conductivity and semiconductor sensing on the same module footprint, so one design carries a ppm toxic channel and a %LEL combustible channel together.
One board instead of four
Multi-channel modules replace stacked single-gas boards, four sets of wiring and four mounting points with one connector. That is less assembly labour and fewer failure points per instrument.
Built for moving platforms
Threaded aluminium barrels, gold-plated contacts and vibration-tolerant structures for quadruped robots, UAVs and handheld terminals, where a box-shaped lab sensor will not survive.
Before you pick a model
Three guides on the decisions that come first: which sensing principle, where to set the alarm, and which certificate actually applies.
Compliance
China Ex, ATEX and IECEx: what the marking on a detector actually tells you
Three certification systems look similar on a datasheet and are not interchangeable. This is how to read the marking and check the paperwork behind it.
Read the guide →Installation
Why 10% LEL and 25% LEL are both correct alarm setpoints
Two numbers appear on almost every combustible gas detector, and they are not competing recommendations. They do different jobs, and conflating them is how alarms end up bypassed.
Read the guide →Installation
Why confined space testing follows O2, LEL, H2S, CO in that order
The order on a four-gas instrument is not alphabetical or traditional. It runs from the hazard that kills fastest to the one that kills slowest, and one channel cannot be trusted until another has been read.
Read the guide →Installation
IP65 and IP66 differ by one digit and one washdown hose
The first digit is dust and both grades pass it. The second digit is water, and the gap between a 12.5 litre jet and a 100 litre jet is the gap between a hose and a pressure washer.
Read the guide →Maintenance
Why calibration needs a certified gas, not the air in the room
Zeroing in ambient air assumes the ambient air contains nothing. In a plant it usually does. Span needs a concentration that someone has measured and certified, or the instrument is being told a number that is not true.
Read the guide →Maintenance
Finding a duplicate Modbus address without pulling the loop apart
A duplicated address does not stop the bus. It produces one garbled reply and a working system, which is why it survives commissioning. The symptom is intermittent, so the diagnosis has to be systematic.
Read the guide →Maintenance
What a gas sensor costs over five years, not at the PO
A cell that costs half as much and lasts a third as long costs more. Five-year cost is dominated by replacement interval, calibration labour and the cost of the day it stops working.
Read the guide →Selection
Choosing the sensing principle before you choose the model
Four principles cover most industrial gas detection. Picking the wrong one gives readings that look plausible and are wrong, so the decision comes before the model number.
Read the guide →Selection
Twelve questions to ask a gas detection OEM before you send a PO
Most of these take one email to answer. The four that matter most are the ones about certification ownership, firmware control, tooling and support, and they are the four buyers ask least often.
Read the guide →Selection
Why a wider measuring range is not a safer one
Specifying 0-1000 ppm where 0-100 ppm would do costs accuracy exactly where the alarm sits, and can hide a leak until it is large. Range selection is an accuracy decision.
Read the guide →Tell us the gas, the range and the enclosure.
We reply with a model recommendation, a datasheet and a price within one working day.