LoRaWAN® Gas Sensors: H₂S, NH₃, O₂ & Ethylene

An electrochemical gas cell on a battery-powered radio node. It measures the concentration of one gas in the air around it, in ppm or percent, and sends the reading over LoRaWAN® kilometres to a gateway, with threshold alerts and no cable or SIM at the point. Macnman makes four: the LH2S X1 for hydrogen sulphide, the L Odor X2 for ammonia and hydrogen sulphide together, the LOXGS X1 for oxygen and the LC2H4 X1 for ethylene.

Start from the gas and the place. Sewers, STPs, biogas and oil and gas sites are hydrogen sulphide: the LH2S X1. Odour at a fence line, a composting yard or a livestock shed is ammonia and hydrogen sulphide together: the L Odor X2. Confined spaces, cylinder stores and inert-gas lines are oxygen: the LOXGS X1. Ripening rooms and produce stores are ethylene: the LC2H4 X1. Indoor air in offices and classrooms is carbon dioxide: the MacSync LCO2 X1 on its own page.

From the datasheets: the LH2S X1 reads H₂S from 0 to 100 ppm (500 ppm maximum) at 0.1 ppm resolution with repeatability under 2 % and zero drift of 0.2 ppm or less. The L Odor X2 adds an ammonia cell reading 0–100 ppm (200 maximum) at 0.5 ppm with repeatability under 10 %. The LOXGS X1 reads oxygen 0–30 % vol at 0.1 % with a response time of 15 seconds or better. The LC2H4 X1 reads ethylene 0–100 ppm (200 maximum) at 0.5 ppm with 1 % repeatability and a response under 30 seconds.

No. The MacSync gas sensors are monitoring and alerting devices that report on a sampling interval over LoRaWAN®. No explosion-protection, fixed-detector or personal-monitor certification is claimed, and the alert latency is the sampling interval, from one minute, not seconds. Where law, an entry permit or a safety case requires a certified detector or a portable test, keep it; these sensors add coverage at the many points those never reach and the continuous record.

No. The MacSync gas sensors carry WPC compliance for the radio and RoHS conformity, and nothing else is claimed. They are not approved for classified hazardous zones where explosion-protected equipment is required; use them in unclassified areas, and keep approved equipment where the area classification demands it.

No. The node has one internal status LED and no buzzer, relay or local display; the alert goes to your platform over LoRaWAN® within the sampling interval, and a MacSet controller on the same network can switch a fan or a damper. A local audible alarm where people work is a certified detector's job.

Within the sampling interval you set, from 1 minute to 24 hours. In event or hybrid mode the node reports the moment a sample crosses the low or high limit, so an alert reaches the platform in minutes. That suits monitoring a wet well, a yard or a store; a seconds-fast alarm in a place people are working is a certified fixed detector's job.

No. The four cells are hydrogen sulphide, ammonia, oxygen and ethylene; there is no flammable-gas (LEL), methane, LPG, carbon monoxide or hydrogen cell in the family, and nothing on this page is a gas-leak detector. For carbon dioxide, the MacSync LCO2 X1 has its own page.

Yes: the LH2S X1 is built for wet wells, pumping stations, inlet works, sludge yards and chambers, mounted low where hydrogen sulphide collects, on a battery rated for years. It logs 0.1 ppm steps and alerts at the site's limit; the Factories Act Second Schedule cites 10 ppm time-weighted and 15 ppm short-term, and the entry permit still rests on a portable test.

Yes: the L Odor X2 reads ammonia 0–100 ppm at 0.5 ppm, mounted at bird or animal height, and through a MacSet controller the reading can drive the fans. Poultry guidance commonly keeps shed air under 25 ppm. The ammonia cell's drift band is wide against its resolution, so it is a trend and ventilation instrument, not a low-ppm hygiene meter.

It logs oxygen in a pit, a tank, a cylinder store or an inert-gas room between entries, in 0.1 % steps, with limits at the usual 19.5 % and 23.5 % vol, so depletion after a purge or a leak is seen in minutes from the control room. It does not replace the pre-entry test with a calibrated portable instrument that a permit requires.

No. The LOXGS X1 reads oxygen in air, 0–30 % by volume, for confined spaces, cylinder stores and inert-gas rooms. Dissolved oxygen in a tank, an aeration basin or a fish pond is a different instrument; ask us about water-quality probes on the MacSync RS485 converter.

Yes, for the ranges those rooms use. Banana and mango ripening rooms are dosed in the tens to low hundreds of ppm, within the LC2H4 X1's 0–100 ppm range at 0.5 ppm resolution, so a dose that reached and held its set point is proven by the record. Ethylene-sensitive storage, where fractions of a ppm matter, needs a different instrument class; the sensor shows a drift upward, not the sub-ppm figure.

No. The L Odor X2 on this page reports ammonia and hydrogen sulphide concentrations in ppm from two cells, for fence lines, yards and sheds. The MacSync L Odor X1 on its own page reports a qualitative odour level for cleaning a washroom on demand. Same company, different jobs.

The datasheets state an expected cell life of about two years for H₂S, ammonia and oxygen and three years for ethylene, after which the cell is replaced, and factory calibration for the H₂S, ammonia and oxygen cells. They do not state a field calibration interval; the practice is a bump test or a comparison against a calibrated portable at commissioning and on the schedule the site's safety procedure sets, recorded with the data.

The datasheets do not publish cross-sensitivity tables; the ethylene cell states a filter for SOₓ, NOₓ and H₂S, and ammonia cells of this type commonly respond to H₂S and amines. Where gases occur in mixtures, read the sensor beside a calibrated portable at commissioning and treat the reading as a trend for that gas mixture; where a pure figure for one gas is required, say so when ordering.

The datasheets state factory calibration for the H₂S, ammonia and oxygen cells and an expected cell life of two to three years; they do not state a field recalibration service or interval, and this page does not claim one. Ask when ordering and we confirm in writing what Macnman offers from Pune for calibration checks and cell replacement.

At the height the gas collects and in the air it should sample. Hydrogen sulphide is heavier than air: mount low in a wet well or chamber, above the water line. Ammonia is lighter: mount high in a shed. Oxygen and ethylene are read at breathing or produce height. Keep it out of wash-down spray, direct exhaust that dilutes the reading and sunlight on the enclosure.

The 19 Ah battery variants are rated about 2 years at 5-minute reports, 4 years at 15-minute reports and 7 or more years at hourly reports (datasheet estimates); event reporting during an excursion adds uplinks. The DC variants run from 9–36 V at the point. Battery level is sent in every uplink.

The node is IP65 with an IP67 option and rated from −40 to +80 °C; the ethylene cell is rated −20 to +50 °C. A deep chamber with a metal lid is served by an indoor gateway nearby or a node near the opening, and a cold store by a gateway in the corridor; the Maya app's Ping test confirms the link before the lid or the door closes.

Through a controller on the same network, yes. A MacSet LX1 starts the fan or closes the damper on the rule your platform sends it, and the MacTalk variants talk device to device to a MacSet with no gateway on site, so an ammonia limit can run the shed's ventilation on a farm with no network at all.

Kilometres, depending on terrain, chambers and antenna height. The node transmits at 23 dBm with −137 dBm sensitivity on LoRaWAN®; a MacLink Gen-2 gateway on an STP's admin block or a plant building typically covers the works and the chambers nearby. The coverage calculator gives a first estimate and the Maya app's Ping test confirms each point.

Yes. The sensors join any LoRaWAN® v1.0.4 network server — ChirpStack, The Things Network, Orbiwise, Netmore, MQTT platforms or a private LNS — by OTAA with pre-loaded keys, and the readings reach your plant SCADA, the utility's control room, an ICCC or a dashboard over MQTT or HTTPS. There is no mandatory Macnman cloud and no subscription.

IN865 for India, plus RU864, EU868, US915, AU915, KR920 and AS923, set when ordering. LoRaWAN in India uses the delicensed 865–867 MHz band, so a utility, a plant or a farm runs its own gateway without a spectrum licence; the devices are WPC compliant and RoHS conforming.

The gas concentration (two for the L Odor X2), event flags on threshold crossings and the battery level, in an AES-128 encrypted LoRaWAN® uplink, periodic or on an event. Decoding is documented with the product; tell us your network server and we send the decoder for it.

The data is yours. The sensor sends to your own network server and from there to the SCADA, ICCC or dashboard you choose, over MQTT or HTTPS. Macnman supplies the hardware, the documentation and the decoder, not a mandatory cloud.

Mount the node with the supplied clip and screws at the height the gas collects; the DC variant wires to the site's 9–36 V supply. Pair over Bluetooth with the Maya app to set the intervals, the limits per gas and the LoRaWAN class, read the live value beside a portable instrument, run a Ping to confirm the gateway, and the device joins by OTAA. No trench, no laptop.

The MacSync gas sensor node, a mounting clip, mounting screws, the user manual and the warranty card. The IP68 cable extender and a power adapter are optional accessories ordered separately.

Yes. The MacSync gas sensors are designed and manufactured in Pune, Maharashtra. They are WPC compliant for the IN865 band and conform to RoHS; the datasheets state both. No explosion-protection, fixed-detector or personal-monitor certification is claimed.

Yes. The four sensors share the node, the radio and the decoder with the MacSync CO₂ sensor and the temperature and humidity sensor, so an STP runs H₂S at the works, NH₃ and H₂S at the fence line and oxygen in the pits, and a packhouse runs ethylene with temperature and humidity, all on one MacLink gateway and one dashboard.

Four lines, and the sensor is only one: the number of points, which depends on the chambers, yards and rooms that matter; battery or DC at each; the gateway, usually one per site plus one for a far corner or a deep chamber; and the integration into the SCADA or platform you run. Cell replacement every two to three years is the recurring line. To quote, send the list of points with the gas and the concentration you expect at each, what the reading must do (log, alert, drive a fan, feed SCADA), whether there is power at each point, whether a LoRaWAN gateway and network server already exist, and the platform the data should reach. With that we confirm the sensors, the variants, the count and the gateway position.

Yes, and it is the recommended way in: three or four sensors on the points that worry the site most, one gateway, your own network server, through one season, with a portable instrument read beside them. The pilot kit on this site is that set; the rest of the points join the same gateway afterwards.