The **KV-B2-R/CE** is a specialized electronic expansion module produced by **Keyence** for their KV series Programmable Logic Controllers (PLCs). It is specifically a **Relay Output Module** designed to interface a low-voltage controller with high-voltage or high-current external devices. --- ### 1. Key Technical Specifications The "R" in the model name indicates **Relay**, and "CE" indicates compliance with European safety standards. | Feature | Specification | | :--- | :--- | | **Output Type** | Relay (Electromechanical) | | **Number of Outputs** | 2 Points | | **Common Type** | Independent (1 point per common) | | **Rated Load** | 30 VDC, 2A / 250 VAC, 2A | | **Minimum Load** | 5 VDC, 10 mA | | **Response Time** | ON: 10 ms max / OFF: 10 ms max | | **Electrical Life** | 100,000 cycles or more (Rated load) | | **Mechanical Life** | 20 million cycles or more | --- ### 2. Internal Electronic Components The KV-B2-R/CE consists of several critical layers of electronic circuitry to ensure safety and functionality: #### A. Photocoupler Isolation To protect the sensitive CPU of the PLC from electrical noise or surges on the output side, the module uses **optical isolation**. An LED triggers a light-sensitive transistor, ensuring there is no physical electrical connection between the internal logic and the output terminal. #### B. Electromagnetic Relays Unlike transistor modules, this unit uses physical coils and contacts. * **Pros:** Can handle both AC and DC; higher current capacity. * **Cons:** Slower switching speeds and a finite lifespan due to mechanical wear. #### C. Snubber Circuits / Varistors The module typically includes internal protection components to suppress "arcing" (sparks) that occur when an inductive load (like a motor or solenoid) is turned off. --- ### 3. Terminal Connection Diagram The module usually features a screw-terminal block. Because the outputs are independent, you can switch different voltages on each terminal. ```text Terminal [ 1 ] ----> [ Relay Contact 1 ] ----> Output 1 (L/+) Terminal [ 2 ] ----> [ Relay Contact 1 ] ----> COM 1 (N/-) Terminal [ 3 ] ----> [ Relay Contact 2 ] ----> Output 2 (L/+) Terminal [ 4 ] ----> [ Relay Contact 2 ] ----> COM 2 (N/-) ``` --- ### 4. Safety and Compliance The **CE** marking signifies that the electronic design meets: * **EMC Directive:** Limits electromagnetic interference. * **Low Voltage Directive (LVD):** Ensures the insulation and physical housing can safely handle up to 250V AC without risk to the user. ---