HSA503K3J is a 50-watt aluminium housed power resistor from the TE Connectivity HS Series, engineered for reliable high-power dissipation in compact form factors. The resistor delivers 50 watts dissipation at 25°C with a standard heatsink and 20 watts without heatsink, with an operating temperature range of -55°C to +200°C. It features a maximum working voltage of 1250 volts (DC or AC rms), an isolation voltage of 2500 volts (DC or AC peak), and supports ohmic values from 0.01 ohms to 100 kilohms with ±5% standard tolerance and ±1% stability over 1000 hours. The resistor is mounted on a standard heatsink with 53,500 mm² area and 1 mm thickness, utilizing 2 mounting holes for secure installation. Common applications include braking resistors, balancing resistors, capacitor charging and discharging circuits, crowbar protection, and general electrical machinery use, where proven reliability and thermal management are essential.