The **RTS-2A4-R/E** is a high-performance **rotary tension sensor** (often referred to as a tension transducer or load cell) manufactured by **Mitsubishi Electric**. It is primarily used in web tension control systems to monitor the tension of materials like paper, film, foil, or textiles during winding or unwinding processes. --- ### 1. Key Technical Specifications Below are the electronic and mechanical characteristics of the device: | Parameter | Specification | | :--- | :--- | | **Rated Load (Capacity)** | 200 N (Approx. 20 kgf) | | **Excitation Voltage** | 5V to 10V DC | | **Output Signal** | Millivolt (mV/V) - Analog | | **Bridge Resistance** | 350 $\Omega$ (Standard Strain Gauge Bridge) | | **Accuracy Class** | $\pm$ 0.5% of Full Scale | | **Installation Style** | Flange mounted / Pillow block | --- ### 2. Internal Electronic Components The device operates on the principle of **strain measurement**. Here is a breakdown of its internal electronic structure: #### A. Wheatstone Bridge Circuit The core of the RTS-2A4-R/E is a **Wheatstone Bridge** consisting of four strain gauges. - **Function:** When tension is applied to the roller shaft attached to the sensor, the internal metallic element deforms slightly. - **Result:** This changes the resistance of the gauges, converting mechanical force into a proportional electrical differential voltage. #### B. Temperature Compensation Resistors To ensure accuracy in industrial environments, the sensor includes internal resistors that compensate for thermal expansion. This prevents "zero-drift" when the factory floor temperature fluctuates. #### C. Electrical Interface (R/E Designation) - **Connector Type:** Typically features a circular multi-pin connector or a hardwired shielded cable. - **Shielding:** The internal wiring is heavily shielded to prevent Electromagnetic Interference (EMI) from nearby motors or VFDs (Variable Frequency Drives). --- ### 3. System Integration Since the output is a low-level analog signal (mV), it cannot be used directly by a PLC. It requires an intermediary: 1. **Tension Amplifier/Controller:** (e.g., Mitsubishi LM-10TA). This device provides the excitation voltage and amplifies the mV signal to 0-10V or 4-20mA. 2. **A/D Converter:** The amplified signal is then sent to a PLC (Programmable Logic Controller) for closed-loop feedback. --- ### 4. Maintenance & Safety Features * **Mechanical Stoppers:** The internal electronics are protected by physical stoppers that prevent the strain gauges from snapping if an accidental overload occurs (up to 500% of rated load). * **Dust/Water Protection:** Usually rated for industrial environments, protecting the sensitive bridge circuit from contaminants.