LEFOO LFG103 Indoor CO Transmitter
Indoor carbon monoxide gas transmitter for occupied-building applications.
Manufacturer: LEFOO
Measurement / function: CO
Primary Manufacturer Source
Official model details or catalog →
The latest configuration, power requirements, outputs and exact technical specifications must be checked against the current manufacturer datasheet.
LFG103 — indoor CO versus CO₂
LFG103 measures carbon monoxide, which is a toxic combustion gas; it must not be confused with carbon dioxide sensors used for demand-controlled ventilation. The maker’s exact ordering details should confirm CO ppm range, output, calibration and any audible relay or display options. For indoor parking or boiler-room use, place the detector according to likely release paths and approved site safety design. A standard model does not inherit Ex approvals from unrelated LEFOO lines.
LFG103 — indoor electrochemical CO, relay and dual signal — engineering details
Hardware output variants, sensor channels and the original maker’s rated operating environment must be matched with the actual supplied part number.
| Technical parameter | Original manufacturer data | Application consequence |
|---|---|---|
| Gas / range | Electrochemical CO; factory options 0–100, 0–250 or 0–400 ppm | Lower CO spans can provide different useful low-level resolution than LFG101 0–1,000 ppm. |
| Accuracy and response | ±5% full scale; t90 ≤60 s after ~2 min preheat | Slower than LFG101’s ≤15 s specification; neither is universal. |
| Electrical supply | 15–36 V DC or 24 V AC ±20% | Use isolated AC transformer with RS485 output as maker requests. |
| Analog outputs | 4–20 mA and 0–10 V on supported hardware; RS485 offered in product family | Interface pin mapping/analog calibration depend on exact order code. |
| Local contact | Configurable SPDT relay, 3 A at 30 V DC or 250 V AC | Relay rating is a maximum control contact rating, not a license to directly switch large fan motors. |
| Mechanical installation | Indoor wall/86-type box, PC housing; IP30 | Not equivalent to LFG101’s more rugged IP6x wall housing. |
| Environment | 0–50 °C / 15–90%RH continuous, with broader intermittent envelope | Intermittent survival conditions are not full-accuracy measurement conditions. |
| Sensor life | Typical electrochemical element life of five years | Calibrate and test CO response; lifetime is not an independent certified alarm guarantee. |
Commissioning and maintenance
LEFOO’s LFG103 is a low-range room CO transmitter with a configurable local relay; its gas calibration should be matched to parking/occupant exposure monitoring requirements. In contrast the LFG101 wall model offers up to 1,000 ppm and a faster nominal response. An indoor relay can interface a properly sized control-panel input or fan contactor coil, not directly a large ventilation motor without load engineering. Both CO concentration and network/relay faults require fail-safe supervision. Confirm the requested AC supply isolation with Modbus models and exact terminal diagram.
Original manufacturer source: LEFOO exact model product specifications. Exact variant documentation must govern installation and certification.
AirAlign product-level technical review — 25 October 2026. Independent safety/Ex/product warranty validation still pending.