![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
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Amazon.com: Yoamp Nylon Braided USB C Charge Cable for Dell Laptop Charger 19.5v 3.33a 65w 2.31a 45w Small tip with pin, Male USB C Adapter Connector Charging Cable for Dell Power Supply (
![Amazon.com: 130W 90W Charger for Dell Inspiron Vostro 16 7610 7620 P107F001 P117F003 P117F004 Laptop 19.5V 6.67A 4.62A Power Supply Adapter Cord : Electronics Amazon.com: 130W 90W Charger for Dell Inspiron Vostro 16 7610 7620 P107F001 P117F003 P117F004 Laptop 19.5V 6.67A 4.62A Power Supply Adapter Cord : Electronics](https://m.media-amazon.com/images/I/61+Da5XMnHL._AC_UF894,1000_QL80_.jpg)
Amazon.com: 130W 90W Charger for Dell Inspiron Vostro 16 7610 7620 P107F001 P117F003 P117F004 Laptop 19.5V 6.67A 4.62A Power Supply Adapter Cord : Electronics
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
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