The Mettler Toledo M400 PA Two-Wire is a single-channel, multi-parameter process transmitter for incorporating analytical measurements into PROFIBUS PA control networks.
Its mixed-mode input supports compatible analog and digital ISM sensors, allowing one transmitter platform to be configured for different process measurement requirements.
Depending on the connected sensor, the transmitter supports pH/ORP, pH/pNa, conductivity, dissolved oxygen, gas-phase oxygen, dissolved carbon dioxide and ozone measurement.

The ½ DIN unit has an IP66-rated enclosure and is available in configurations for hazardous and non-hazardous area installations, subject to the applicable approvals and installation requirements.
Key Characteristics
- Two-wire, single-channel, multi-parameter process transmitter
- PROFIBUS PA communication for integration with compatible process control and asset-management systems
- Mixed-mode input for compatible analog or digital ISM sensors
- Supports pH/ORP, pH/pNa, conductivity, dissolved oxygen, gas-phase oxygen, dissolved carbon dioxide and ozone measurements, depending on sensor selection
- Provides access to compatible ISM sensor identification and diagnostic information through the fieldbus network
- ½ DIN, IP66-rated enclosure
- Available with approvals for specified hazardous-area installations
Ideal Applications
- Connecting process analytical measurement points to PROFIBUS PA automation networks
- Monitoring pH/ORP, conductivity, oxygen, dissolved carbon dioxide or ozone with a compatible sensor
- Installations transitioning from conventional analog sensors to digital ISM sensor technology
- Applications requiring compatible sensor diagnostics to be incorporated into plant control or asset-management systems
- Process measurement points located in approved hazardous or non-hazardous areas
Parameters
- Conductivity
- Dissolved CO2
- Dissolved Oxygen
- Dissolved Ozone
- Gas-Phase Oxygen
- ORP
- Optical DO
- pH
Communication
- Profibus PA
Product Family Includes
- M400 2XH Type 2
- M400 2H Type 2
- M400 2XH Type 2 ISM
- M400 2H Type 2 ISM
- M400 2XH Type 3
- M400 2XH Type 3 ISM
- M400 FF Two-Wire
- M400 PA Two-Wire
Industries Served
- Chemical Processes
- Food/Beverage Production
- Pharmaceutical/Life Science Production







