Product
TDL1200
Precision tunable diode laser methane analyser — 0–1200 ppm CH₄, with mandatory validity state on every reading
Overview
The TDL1200 is Devlabs' precision methane analyser — a portable instrument designed for continuous CH₄ measurement in the 0–1200 ppm range. It uses Tunable Diode Laser Spectroscopy (TDLAS), a laser-based absorption technique that provides high selectivity for methane and immunity to common interferents — including hydrogen sulphide, which degrades electrochemical sensors in wastewater, biogas, and industrial environments.
Every TDL1200 reading carries a mandatory validity state: valid, degraded, or invalid. This is not a status indicator — it is a first-class output that any downstream system must check before using a reading. The instrument is designed to tell you when a measurement cannot be trusted, whether due to a thermal transient, a filter nearing end-of-life, or a system fault. Device health (ok / degraded / fault) is tracked independently from measurement validity, providing a complete picture of instrument condition at all times.
TDL1200 v2 is currently in active development. A v1 unit has been deployed commercially. v2 instruments are not yet available off-the-shelf — contact Devlabs to discuss deployment requirements and timeline.
Capabilities
Key features
TDLAS measurement technology
Tunable Diode Laser Spectroscopy targets the specific absorption wavelength of methane, providing high selectivity and immunity to common interferents — including hydrogen sulphide, which degrades and confuses electrochemical sensors in wastewater and biogas environments.
Validity state on every reading
Every TDL1200 reading carries a mandatory validity state: valid, degraded, or invalid. This is not a status LED — it is a first-class output that any downstream system must check before using a reading. The instrument will tell you when a measurement cannot be trusted.
Multiple simultaneous data interfaces
RS-485 Modbus RTU, 4–20 mA analogue output, LoRaWAN (via included transmitter), SD card local logging, and a built-in display. All interfaces are available simultaneously — no configuration required to enable them.
Active pump-based sampling
An integrated pump draws sample gas through the measurement cell at a defined flow rate. Pump state, flow rate, filter pressure, and cell temperature are all exposed via Modbus — providing full observability into sampling system health.
Independent device health monitoring
Device health (ok / degraded / fault) is tracked independently from measurement validity. A healthy instrument can report invalid readings; a degraded instrument will report its health state even when readings appear valid.
Portable suitcase form factor
Housed in a rugged suitcase enclosure designed for field survey and semi-permanent deployment. The TDL1200 can be carried to the measurement point, connected to an external DC supply, and left to run unattended.
Specifications
Technical specifications
| Target gas | Methane (CH₄) |
| Measurement principle | Tunable Diode Laser Spectroscopy (TDLAS) |
| Measurement range | 0–1200 ppm CH₄ |
| Stated accuracy | ±2 ppm |
| Thermal transient sensitivity | Up to ±5 ppm excursion when cell temperature changes faster than 3.6 °C/hour — reflected in degraded or invalid validity state |
| Validity state | valid / degraded / invalid — mandatory first-class output on every reading |
| Device health state | ok / degraded / fault — independent of measurement validity |
| Primary interface | RS-485 Modbus RTU |
| Secondary interface | 4–20 mA analogue output |
| Wireless | LoRaWAN (via included DL-LN-485 transmitter) |
| Local | Built-in display + SD card data logging |
| Sampling | Active pump-based — pump state, flow rate, filter pressure, and cell temperature exposed via Modbus |
| Filter | Consumable — replacement interval depends on sample conditions |
| Form factor | Rugged suitcase enclosure, portable and field-deployable |
| Power | External DC supply (no integrated mains power supply or battery) |
| LoRaWAN network server | The Things Industries (TTI) |
| Limitations | Not a certified reference instrument. Not suitable for flue gas or high-concentration CH₄ measurement above 1200 ppm. |
Specifications subject to change without notice. Contact Devlabs for the current datasheet.
Availability
TDL1200 v2 is currently in active development. A v1 unit has been deployed commercially. v2 instruments are not yet available off-the-shelf — contact Devlabs to discuss availability, timeline, and deployment requirements.
Ecosystem
Works alongside
Devlabs data platform
All Devlabs hardware connects to the same cloud platform — one interface for real-time monitoring, alarms, and API access across your entire deployment.
Platform overview →Get in touch
Ready to specify a TDL1200 deployment?
Our team can scope your monitoring requirements, recommend a configuration, and give you an indicative price within 48 hours.