The M400 2XH Type 2 ISM is a single-channel, 2-wire multiparameter transmitter designed for use with compatible digital ISM sensors in demanding process environments.
Its aluminum enclosure and hazardous-area approvals support installation where robust process instrumentation and intrinsic safety are required.
The transmitter supports pH/ORP, pH/pNa, four-electrode conductivity, amperometric dissolved oxygen, optical dissolved oxygen, and dissolved carbon dioxide measurement.
HART communication provides access to measured values, device information, and ISM sensor diagnostic data through compatible asset-management systems and field communicators.

Key Characteristics
- Single-channel, 2-wire configuration for digital ISM sensors
- Supports pH/ORP, pH/pNa, four-electrode conductivity, amperometric dissolved oxygen, optical dissolved oxygen, and dissolved CO2 measurement
- HART communication for measured values, device information, sensor diagnostics, and supported remote instrument functions
- Two isolated 4–20 mA current outputs and two open-collector digital outputs
- Four-key interface with a 4.4-inch display and multilingual operation
- Aluminum die-cast enclosure rated IP66/NEMA 4X
- Hazardous-area certifications for designated Zone 1, Zone 21, and Class I Division 1 installations
Ideal Applications
- Chemical process measurements in hazardous or demanding industrial environments
- Pharmaceutical process analytics using compatible ISM sensors
- pH, ORP, conductivity, and dissolved oxygen measurement in process vessels and piping systems
- Dissolved CO2 measurement with compatible pharmaceutical process sensors
- Installations requiring 2-wire loop power and HART communication
- Applications where ISM sensor identification and diagnostic information are incorporated into the measurement system
Parameters
- Conductivity
- Dissolved CO2
- Dissolved Oxygen
- ORP
- pH
Communication
- HART
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
Industries Served
- Chemical Processes
- Pharmaceutical/Life Science Production






