General
Number of channels	8
Interface	NAMUR
Degree of protection	Ex i
Norm	DIN EN 50227
Colour	Blue
Function	digital input

The WAGO 750-439 is an 8-channel digital input terminal for NAMUR sensors in an intrinsically safe (Ex i) version. It is designed for the safe acquisition of proximity sensors in industrial applications, particularly in explosive atmospheres, and is compliant with DIN EN 50227. The terminal is finished in blue, enabling optical identification in the enclosure and improving signal assignment.

Applications
This terminal is intended for use in systems with enhanced safety requirements, particularly in areas where explosion hazards exist. It is suitable for connecting NAMUR proximity sensors, which are used for example in process automation, conveyor technology, or machine control. The intrinsically safe design (Ex i) allows use in Zone 1 and Zone 2 according to applicable standards for explosion-protected electrical equipment.

Functions and Features in Detail
The terminal features eight independent inputs, each capable of connecting to a NAMUR sensor. NAMUR sensors are specifically designed for use in explosive environments and operate with an open or closed contact, signaled via a resistance value (typically 1 kΩ to 10 kΩ). The terminal detects these states and converts them into digital input signals for the control system. The blue color serves as a visual identifier and supports quick recognition in the enclosure.

Technology Explained Simply
The intrinsically safe design (Ex i) means the terminal is constructed so that under normal operating conditions it does not release any ignition energy that could trigger an explosion. This is achieved by limiting voltage, current, and power. Compliance with DIN EN 50227 ensures the terminal meets requirements for electrical safety and signal transmission for NAMUR sensors. The terminal is designed for use in industrial control systems with modular rail mounting (e.g., DIN rail).

Compatibility and Accessories
The terminal is compatible with NAMUR sensors specified according to DIN EN 50227. It can be combined with other WAGO modules, particularly with power supplies such as the 750-625/000-001 or 750-606, which provide 24 V DC. Suitable mounting rails include the 210-112 or 210-113. For module identification, quick labeling systems such as the 248-501/000-023 or 248-501/000-005 can be used. Shielding terminal clamps like the 790-108 or 790-216 support proper cabling and shielding.

Mounting and Installation
The terminal is mounted on a DIN rail with a rail width of 35 mm. Installation is done by simply clipping the terminal onto the rail. Sensor wiring is connected via the designated terminal connectors. Power supply is provided through the appropriate supply lines connected to the terminal. Installation takes place in a closed enclosure, which provides the necessary protection against environmental conditions and mechanical influences.

Advantages in Operation
The terminal provides reliable and safe signal transmission from NAMUR sensors in explosive environments. Its modular design allows flexible expansion of the control system. The clear color marking (blue) simplifies maintenance and module identification. Compliance with DIN EN 50227 and the intrinsically safe design (Ex i) ensure safety requirements are met in critical applications. The terminal is designed for industrial environments with high demands on reliability and safety.