Cord AWG size for big routers

[Alex Zeller]

The national electrical code doesn't apply to cords on devices. An engineer that designed it is free to choose what size wire to use and how thick the insulation on the wire should be. It's why you'll find a wire gauge that would be too small by code on something like a router.

[Jim Becker]

Alex, wouldn't UL and similar organizations in other countries have a say on approving the design? It's a bit hard to sell products that don't have those kinds of approvals.

[Edward Weber]

Alex, wouldn't UL and similar organizations in other countries have a say on approving the design? It's a bit hard to sell products that don't have those kinds of approvals.

Exactly my thoughts.
A device, used properly, shouldn't fail due to electrical issues. It would not get UL certified if it did.

[Rod Sheridan]

Where I live, 14AWG flexible cord with 2 current carrying conductors is rated at 18 amperes……Regards, Rod

[Mike Cutler]

We're kind of over thinking this here.
For an extension cord, it's really the length, as well as the awg, that you're looking at.Hopefully the OP already has what he needs.
Under 25', a 16awg extension cord will run that router just fine. Longer than 25' and you would want to consider stepping up to 14awg.
I would be willing to bet that the internal wiring, and provided cords, on the largest routers on the market is probably 16awg internally, and 14awg for the cord, at best.

[Alex Zeller]

UL certification is optional. They also test based on what the company specifies. For example if the company says it's router is designed for 15 minutes of continuous use with 45 minutes of rest that's how they assume it'll be used. UL doesn't try to find the breaking point. They do try to see if a item meets industry standards but that's not easy. For example routers from different manufacturers will have different ratings.

The NEC are written assuming the worst case. Wiring size is based the temperature the wire will while carrying the maximum current going through the wires 100% of the time (ampacity).