The **JR28-R-DLSP115** refers to a specific series of Thermal Overload Relays, typically manufactured by brands like Chint or similar industrial electrical suppliers. These components are essential for motor protection in industrial automation and power distribution. --- ### ## 1. Technical Specifications The following table summarizes the key electrical characteristics of the JR28 series (specifically the 115 model variants). | Parameter | Description | | :--- | :--- | | **Series** | JR28-R (Plug-in or Independent Mount) | | **Model Frame** | 115 (Large Frame Size) | | **Adjustment Range** | Typically ranges within 80A to 115A (Specific to suffix) | | **Rated Voltage (Ue)** | 690V AC | | **Rated Insulation Voltage (Ui)** | 1000V | | **Trip Class** | 10A (Standard motor protection) | | **Auxiliary Contacts** | 1 NO (Normally Open) + 1 NC (Normally Closed) | --- ### ## 2. Core Functional Components The "electronic" logic of this device is largely electromechanical, utilizing the properties of bimetallic strips to sense heat. 1. **Bimetallic Strips:** The heart of the unit. As current flows through these strips, they heat up. If the current exceeds the set threshold, the metal strips bend at a predictable rate due to thermal expansion. 2. **Differential Mechanism:** The "R" in the model name often signifies **Phase Failure Protection**. If one phase draws significantly less current than the others (indicating a dropped phase), the differential mechanism triggers the trip early to prevent motor burnout. 3. **Adjustment Dial:** A potentiometer-style dial on the front that allows the user to set the precise Full Load Amps (FLA) of the motor. 4. **Auxiliary Terminals:** * **95-96 (NC):** Usually wired in series with the contactor coil to cut power upon a fault. * **97-98 (NO):** Used for alarm signaling or PLC input to notify the system of a trip. --- ### ## 3. Wiring Configuration The JR28-R is usually paired with a **CJX2 series contactor**. Below is a basic representation of the control circuit wiring. ```mermaid graph TD A[L1/L2/L3 Power] --> B[CJX2 Contactor] B --> C[JR28-R Overload Relay] C --> D[Industrial Motor] subgraph Control_Circuit E[Stop Button] --- F[95 NC Terminal 96] F --- G[Contactor Coil A1] end ``` --- ### ## 4. Key Features * **Manual/Auto Reset:** Features a toggle to choose between manual reset (requires physical intervention) and auto reset (cools down and resets). * **Temperature Compensation:** Designed to operate consistently in ambient temperatures ranging from -5°C to +40°C. * **Test/Stop Buttons:** Includes a red button to manually trip the device for testing and a stop button to temporarily open the NC contacts.