![power supply - 3 wires on a (bipolar) DC plug - what are they for? - Electrical Engineering Stack Exchange power supply - 3 wires on a (bipolar) DC plug - what are they for? - Electrical Engineering Stack Exchange](https://i.stack.imgur.com/iPsc1.jpg)
power supply - 3 wires on a (bipolar) DC plug - what are they for? - Electrical Engineering Stack Exchange
![DELL Laptop Charger Big Pin 65 W Adapter, Output Voltage: 19.5 Volts, Input Voltage: 240V at Rs 600/piece in Kolkata DELL Laptop Charger Big Pin 65 W Adapter, Output Voltage: 19.5 Volts, Input Voltage: 240V at Rs 600/piece in Kolkata](http://5.imimg.com/data5/SELLER/Default/2022/6/UN/NQ/ES/4269059/dell-laptop-charger-big-pin-65-w-adapter-250x250.jpg)
DELL Laptop Charger Big Pin 65 W Adapter, Output Voltage: 19.5 Volts, Input Voltage: 240V at Rs 600/piece in Kolkata
How does a Dell laptop charger with a pin of the same wattage & specs which fits perfectly into an HP not work because it knows it is not an HP charger
![Dell Original 65W Laptop Adapter With 4.5mm Socket (Slim Pin), Input Voltage: 110 To 240 Vac, Ac at Rs 1250/piece in Kolkata Dell Original 65W Laptop Adapter With 4.5mm Socket (Slim Pin), Input Voltage: 110 To 240 Vac, Ac at Rs 1250/piece in Kolkata](http://5.imimg.com/data5/SELLER/Default/2020/10/UF/LJ/QU/10464536/dell-original-65w-laptop-adapter-with-4-5mm-socket-slim-pin-.jpg)
Dell Original 65W Laptop Adapter With 4.5mm Socket (Slim Pin), Input Voltage: 110 To 240 Vac, Ac at Rs 1250/piece in Kolkata
![laptop - Hacking Dell charger to run directly from an external 19.5V power source - Electrical Engineering Stack Exchange laptop - Hacking Dell charger to run directly from an external 19.5V power source - Electrical Engineering Stack Exchange](https://i.stack.imgur.com/IIC6A.png)