The **M2PA-51-R2/UL** is a specific electronic component within the industrial automation and control category, manufactured by **Omron**. It is a sub-assembly component, specifically a **Replacement Socket/Switch Unit** for the M2PA series of square push-button switches. Below is a detailed breakdown of its electronic and mechanical specifications. --- ### 1. General Overview The M2PA series consists of square, lighted push-button switches designed for panel mounting. The **M2PA-51-R2/UL** part number typically refers to the **Switch Unit** (the mechanical/electrical backend) rather than the lens or the housing. ### 2. Technical Specifications | Parameter | Specification | | :--- | :--- | | **Manufacturer** | Omron Automation & Safety | | **Series** | M2PA (Square Type) | | **Contact Form** | DPDT (Double Pole Double Throw) | | **Switch Operation** | Alternate (Push-on, Push-off) | | **Rated Voltage** | 125 VAC / 250 VAC | | **Current Rating** | 5A at 125 VAC / 3A at 250 VAC | | **Certification** | UL (Underwriters Laboratories) Recognized | | **Termination Style** | Solder Terminals | --- ### 3. Key Electronic Features * **DPDT Configuration:** This unit allows the user to control two separate circuits simultaneously. Each pole has a Normally Open (NO) and Normally Closed (NC) contact. * **Alternate Action:** Unlike "momentary" switches that spring back immediately, this "alternate" unit stays in the actuated position until pressed a second time (Latching). * **Gold/Silver Contacts:** These units often utilize silver-alloy contacts to handle higher current loads while maintaining low electrical resistance over thousands of cycles. * **UL Approval:** The "/UL" suffix indicates that the component meets specific safety standards for the North American market, ensuring fire and shock resistance parameters are met. ### 4. Component Structure The M2PA system is modular. To have a functional switch, the M2PA-51-R2/UL is usually combined with: 1. **Display Unit:** The colored lens (Red, Green, Yellow, etc.). 2. **Illumination:** LED or Incandescent lamps (the socket accepts the bulb). 3. **Housing:** The outer frame that holds the unit into the control panel. --- ### 5. Application Areas * **Industrial Control Panels:** Used as "Power On" or "Mode Selection" switches. * **Telecommunications:** Signal routing and status indication. * **Test Equipment:** Manual interface for toggling device states.