TPEL thermal fuses in the TH77 HOL series permanently open the circuit when the temperature reaches 77°C, providing irreversible overtemperature protection. Sold in packs of 5, they are suitable for transformers, ventilation systems, electric fans, low-power motors, chargers, electronic ballasts, capacitors, and various heating systems.

The HOL (hollow lead) form factor is compatible with PCB through-hole mounting and direct in-line wiring. The 77°C trip point and 55°C holding temperature are suited to equipment that runs noticeably warm under normal load before reaching a fault condition.

Key Features

• Rated functioning temperature (TF): 77°C — opens permanently at this temperature
• Fusing-off temperature: 73°C ±2°C
• Holding temperature (TC): 55°C — safe continuous operating temperature
• Maximum temperature limit: 120°C
• Rated voltage: 250V AC
• Rated current: 10A

Product Benefits

• 77°C trip point suits equipment that routinely operates in the 55–73°C range without triggering
• Non-resettable action provides a permanent, tamper-proof open-circuit record of the fault event
• 10A current rating handles most low-power motor, charger, and ballast applications
• Compact HOL construction integrates into existing PCB and wiring harness designs
• Pack of 5 supports both single-unit replacement and batch maintenance requirements

Technical Specifications

• Model: TH77 HOL
• Brand: TPEL
• Rated Functioning Temperature (TF): 77°C
• Fusing-off Temperature: 73°C ±2°C
• Holding Temperature (TC): 55°C
• Maximum Temperature Limit: 120°C
• Rated Voltage: 250V AC
• Rated Current: 10A
• Pack Quantity: 5 pcs

Why You'll Love It

• High 55°C holding temperature prevents false trips in equipment that runs warm under normal conditions
• 250V/10A rating is widely compatible with low-power appliance protection circuits
• HOL lead format slots into standard PCB layouts without additional adapters
• Package includes 5x TPEL Thermal Fuse 250V 10A 77°C-TH77 HOL