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USB-C can deliver 2000 Watt

Published: 22 November 2021
Last updated: 14 March 2023

USB-C as power connector tested on supporting 2000W

USB-C connectors can support 100W, which is a lot for such a small connector. So, I wanted to investigate how that works. It would be funny to investigate whether even more power could be supported. 

USB-C 24 pin layoutUSB-C 24 pin layout

USB-C is specified for supporting 5A at 20V, that’s make 100W.  The new USB-C Type 2.1 will support 5A at 48V (240W). For the transport of large currents, the contact resistance must be small. I have measured the contact resistance myself and it turns out to be 40mΩ per contact and that is exactly according to the specifications (link). The power lines GND and Vbus, each use 4 contacts in parallel, which brings the resistance to 10mΩ.

The power loss at 5A can be calculated with

P = 2 * I2 * R

P = 2 x 5A2 * 10mΩ = 0.5W

USB C measuring contact resistanceUSB-C measuring contact resistance

USB C measuring contact resistance 10mΩUSB-C measuring contact resistance 10mΩ

USB-C can deliver 2000W, not just 240W

With currents above 5A, the connector will become a bit warmer, and a larger voltage could also not be a big problem. So, I tested the USB-C connector with a 2000W heater at 230VAC. There was no smoke or anything like that coming out of the USB-C connector, it supported the 2000W well. The current in this case is 8.7A and the power loss in the connector is about 1.5W.

You could also connect all 12 contacts in parallel for better supporting high currents and you'll end up with a power loss of just 0.5W at 8.7A, the same as with the specified 5A current.

P = 2 x 8.7A2 * (40mΩ/12) = 0.5W.

USB-C 240W power delivery how does it workUSB-C 240W power delivery how does it work

USB-C can deliver 2000W, not just 240WUSB-C can deliver 2000W, not just 240W

Using USB-C as a 25A power connector

If you connect all 24 contacts in parallel, the total contact resistance becomes 40mΩ/24 = 1.7mΩ. If you accept a power loss of 1W, that is just 2 x the 0.5W discussed above, then the maximum allowable current is √(1W/1.7mΩ) = 25A.

USB-C Port Controller

USB-C Port ControllerUSB-C Port Controller



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