The **W2PP-112R-R2/N** is a specific model of a **Miniature Industrial Power Relay**, commonly used in automation, control panels, and PCB mounting. Below is a detailed breakdown of its electronic components, specifications, and functions. --- ### 1. Technical Specifications The part number follows a specific nomenclature that defines its electrical characteristics: | Parameter | Specification | | :--- | :--- | | **Coil Voltage** | 12V DC (Standard) | | **Contact Configuration** | DPDT (2 Form C) - Double Pole Double Throw | | **Contact Rating** | 5A to 10A (Depending on load type: AC/DC) | | **Mounting Type** | PCB (Through-hole) or Socket Mount | | **Terminal Material** | Silver Alloy (AgNi or AgSnO2) for conductivity | | **Internal Resistance** | Approx. 160Ω - 200Ω (Coil specific) | --- ### 2. Internal Electronic Structure The device consists of three primary sections that work together to switch high-power loads using low-power signals: #### A. The Coil (Input Side) * **Function:** An electromagnetic solenoid. * **Operation:** When 12V DC is applied, current flows through the copper windings, creating a magnetic field. * **Protection Note:** It is highly recommended to use a **flyback diode** (e.g., 1N4148) in parallel with the coil to protect driving transistors from inductive spikes. #### B. The Armature and Spring * **Function:** The mechanical linkage. * **Operation:** The magnetic field pulls the armature toward the core. When power is removed, a precision spring returns the contacts to their "Normally Closed" (NC) position. #### C. The Contact Sets (Output Side) * **DPDT Design:** It features two independent switches controlled by the same coil. * **Common (COM):** The moving part of the switch. * **Normally Open (NO):** Contact is made only when the coil is energized. * **Normally Closed (NC):** Contact is made when the relay is at rest. --- ### 3. Application Use-Cases * **Isolation:** Separating a low-voltage microcontroller (like an Arduino or PLC) from a high-voltage 220V AC motor. * **Signal Routing:** Switching between two different audio or data sources. * **Polarity Reversal:** Using the DPDT configuration to reverse the direction of a DC motor. --- ### 4. Circuit Symbol Representation ```text Coil Contacts (DPDT) +---+ /--- NC1 (1)-| |-(2) (3)-|--- NO1 | L | \--- COM1 +---+ /--- NC2 (4)-|--- NO2 \--- COM2 ```