The 2705-P21C1 is a robust Lighted Push Button Module from the Allen-Bradley Bulletin 2705 series, widely utilized in industrial operator interface applications. This module provides a reliable human-machine interface (HMI) solution, combining tactile operator input with integrated visual feedback. Its design is tailored for integration into control panels where clear, high-visibility signaling and responsive switching are required for machine operation and process control.

Technical Specifications

• Module Type: Lighted Push Button Interface Module.

• Input Interface: Tactile push-button switch with integrated LED illumination.

• Compatibility: Designed for use with Bulletin 2705 Information Display/Operator systems.

• Dimensions: Standard compact modular form factor (approx. 2.0 inches x 2.0 inches face dimensions).

• Weight: Approximately 0.15 kg (0.33 lbs).

• Country of Origin: United States.

Application Fields

🟢 Control Panels: Used extensively as start/stop or alarm acknowledgment buttons on industrial consoles. 🏭 Machine Tooling: Provides localized operator feedback on CNC and automated assembly machinery. ⚠️ Safety Systems: Integrated into emergency status monitoring for immediate visual identification of machine states.

Product Usage Instructions

💡 Installation: Ensure the panel cutout meets the specified dimensions before mounting the module. Secure the locking ring firmly to maintain a NEMA-rated seal. 🛠️ Wiring: Connect the switch contact terminals and the LED power terminals to your PLC I/O or control circuit according to the pinout diagram. ✅ Testing: After installation, activate the control signal to verify that the LED illuminates properly and that the mechanical switch sends the appropriate digital signal to the controller.

Common Questions & Answers

Q: Can the LED bulb inside the 2705-P21C1 be replaced? A: Yes, the light assembly is typically serviceable. However, it is essential to use the exact voltage-rated replacement bulb or LED component to prevent damage to the module circuitry. Q: Is this module suitable for outdoor or washdown environments? A: The 2705-P21C1 is designed for standard industrial panel mounting. Always verify that the front bezel seal is intact and that the panel rating (e.g., NEMA 4/12) is maintained during installation. Q: Why is the button sticking or not depressing fully? A: This is usually caused by an accumulation of debris or oil around the actuator seal. Clean the perimeter of the button with a soft cloth and mild industrial cleaner.

Product Maintenance Instructions

Perform routine checks of the button mechanism to ensure smooth operation and no physical obstruction. Inspect the wiring connections on the rear of the module periodically, as loose connections due to vibration can cause flickering illumination or intermittent signal loss. If the legend plate or button cap becomes faded or scratched, they can typically be replaced without removing the entire module from the panel.

Recommended Similar Models

• 2705-P21C2

• 2705-P21D1

• 2705-P22C1

• 800T-PX16 (Allen-Bradley 800T Series)

• 800H-PRPX (Allen-Bradley 800H Series)