Integrating pneumatic diagnostics directly into the field level, the Beckhoff EPP3744-0041 EtherCAT P Box provides a decentralized interface for both digital signals and direct air pressure measurement. This rugged, IP67-rated module combines four relative pressure inputs, six digital inputs, and two digital outputs into a single compact housing, eliminating the need for protective control enclosures and reducing field wiring complexity.
Key Features
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Unified Power and Data: EtherCAT P technology integrates high-speed communication and dual 24 V DC power supplies (Us for system/sensors and Up for actuators) into a single M8 P-coded connection.
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Direct Pneumatic Interface: Four integrated pressure sensors with 6 mm push-in fittings for direct machine-mount air pressure monitoring.
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Flexible Digital I/O: Six digital inputs (EN 61131-2, Type 1/3) and two short-circuit proof 0.5 A digital outputs handle localized sensor and actuator connections.
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Distributed Clocks: High-precision synchronization support for time-critical industrial automation processes.
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Environmental Resilience: Fully encapsulated IP65/66/67 housing designed to withstand extreme vibration, shock, and wet industrial environments.
Industrial Applications
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Pneumatic System Diagnostics: Real-time pressure drop monitoring and leak detection in localized valve manifolds.
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Robotic End-of-Arm Tooling (EOAT): Lightweight, decentralized I/O and vacuum/pressure sensing directly on robotic arms.
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Packaging and Assembly Lines: Distributed sensor collection and pneumatic cylinder control without localized terminal boxes.
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Material Handling: Vacuum gripper monitoring and localized conveyor control in sorting facilities.
Technical Specifications
| Parameter |
Specification |
| Manufacturer |
Beckhoff Automation GmbH & Co. KG |
| Model / Article Number |
EPP3744-0041 |
| Protocol |
EtherCAT P |
| Bus Interface |
2 x M8 socket, shielded, screw type, P-coded |
| Number of Inputs |
4 x pressure inputs, 6 x digital inputs |
| Number of Outputs |
2 x digital outputs |
| Connection Method (I/O) |
Digital: 4-pin M8; Pressure: 6 mm push-in fitting |
| Measuring Range |
-1 to 1 bar (-15 to 15 psi) / 0 to 1 bar (0 to 15 psi) relative pressure |
| Resolution |
1 mbar per digit |
| Measurement Uncertainty |
3 percent of full scale |
| Conversion Time |
approximately 3.5 ms |
| Nominal Voltage |
24 V DC (-15 percent / +20 percent) |
| Current Consumption (Us) |
100 mA typical |
| Max. Output Current |
0.5 A per channel (short-circuit proof) |
| Electrical Isolation |
500 V |
| Operating Temperature |
-25 to +60 degC |
| Storage Temperature |
-40 to +85 degC |
| Protection Rating |
IP65 / IP66 / IP67 (conforms to EN 60529) |
| Approvals |
CE, UL |
| Country of Origin |
Germany |
| Shipping Weight (Calculated) |
0.35 kg (Net: 0.15 kg) |
| Package Dimensions (Calculated) |
150 x 60 x 40 mm |
Connections and Interfaces
| Connector / Terminal |
Pin / Connection |
Function / Circuit Assignment |
| EtherCAT P (M8 P-coded) |
Pin 1 |
Us+ (24 V DC system and sensor supply) |
| Pin 2 |
Up+ (24 V DC peripheral voltage for actuators) |
| Pin 3 |
Us- (GND for system and sensor supply) |
| Pin 4 |
Up- (GND for peripheral voltage) |
| Digital I/O (M8 4-pin) |
Pin 1 |
+24 V DC sensor supply (derived from Us) |
| Pin 2 |
Input / Output Channel B |
| Pin 3 |
GND |
| Pin 4 |
Input / Output Channel A |
| Pneumatic Ports |
Ports 1 to 4 |
6 mm push-in fittings for relative air pressure measurement |
Empirical Engineering Insights
Alternative Models & Compatibility
The EPP3744-0041 is an EtherCAT P device and must not be connected to standard EtherCAT (EP series) ports without an intermediate junction or injector module (such as the EP9224-0002). Standard EtherCAT uses D-coded M8 connectors, whereas EtherCAT P utilizes P-coded M8 connectors to prevent accidental cross-wiring of combined power and data lines.
Application Pitfalls & Engineering Notes
When deploying the module in high-humidity environments, ensure that the compressed air supplied to the 6 mm pneumatic fittings is thoroughly dried and filtered. Liquid condensation or oil mist entering the internal silicon pressure sensors will cause calibration drift, measurement offsets, or permanent sensor element failure.
Commissioning & Wiring Tips
Always calculate the total current draw of the EtherCAT P segment in TwinCAT 3 before physical commissioning. The combined current for Us and Up must not exceed 3 A per branch. If voltage drops below 20.4 V DC at the end of a daisy chain, install an EP9224 power feed-in box to boost the supply.
Installation Guidelines
CRITICAL WARNING
Disconnect all electrical power sources (Us and Up) and completely depressurize the pneumatic lines before mounting, wiring, or servicing this module. Failure to do so can result in equipment damage, unexpected actuator movement, or physical injury from high-velocity pneumatic tubing ejection.
1
Mount the module to a flat, vibration-resistant machine surface using two M3 screws. Torque to 0.8 Nm.
2
Insert clean, square-cut 6 mm pneumatic tubing into the push-in fittings until it bottoms out securely.
3
Connect the M8 P-coded EtherCAT P cables. Tighten the screw connections to 0.4 Nm to guarantee the IP67 environmental seal.
4
Connect digital sensors and actuators to the M8 I/O ports using shielded cables to minimize electromagnetic interference.