The **M5TS-85-R/BN** is a specific type of thermal switch or thermostat produced by **Uchiya**. It is primarily designed as a safety device to protect electronic circuits and appliances from overheating. --- ### 1. General Specifications The part number can be broken down into its technical characteristics: | Feature | Specification | | :--- | :--- | | **Series** | M5TS (Manual Reset Type) | | **Temperature Setpoint** | 85°C | | **Reset Type** | Manual (Requires physical intervention to restart) | | **Terminal Type** | R/BN (Specific bracket and terminal configuration) | | **Max Voltage/Current** | Typically 250V AC / 10A (Model dependent) | --- ### 2. Key Electronic Components & Functions #### A. Bimetallic Disc The heart of the M5TS is a **bimetallic disc**. This consists of two different metals bonded together. Because these metals expand at different rates when heated, the disc "snaps" at exactly 85°C, physically separating the electrical contacts. #### B. Contact Mechanism (NC - Normally Closed) Under normal operating temperatures, the circuit is closed, allowing current to flow to the heater or motor. When the 85°C threshold is reached, the snap-action mechanism opens the contacts to cut off power. #### C. Manual Reset Button Unlike "Auto-reset" models that turn back on once they cool down, the **M5TS** series features a manual reset. Once tripped, a human operator must physically press a button to re-close the circuit. This is a critical safety feature for devices where a fault (like a jammed motor) must be inspected before restarting. --- ### 3. Common Applications This part is frequently found in industrial and consumer appliances where thermal runaway could cause fire or damage: * **Office Equipment:** Laser printers and photocopiers (fuser assembly). * **Heating Appliances:** Steam cleaners, water heaters, and coffee machines. * **Industrial Power Supplies:** To prevent transformer overheating. --- ### 4. Technical Advantages 1. **Reliability:** The snap-action mechanism ensures a fast break of the circuit, minimizing electrical arcing. 2. **Accuracy:** Uchiya thermostats are known for tight temperature tolerances (typically ±3°C to ±5°C). 3. **Durability:** Designed for high-current loads without premature contact wear.