---- Original Message -----
From: "William Herrin" <bill@herrin.us>
On Wed, Mar 19, 2014 at 11:22 AM, Lamar Owen <lowen@pari.edu> wrote:
Just replacing an L6-20P with an L6-30P on a 20A-listed PDU would be unsafe and (IMO) unwise, since the breaker in the input of the PDU does not protect the flexible cord's conductors from internal overcurrent faults.
Yet an 18 awg PC power cable is perfectly safe when plugged in to a 5-20R on a circuit with a 20 amp breaker. Get real man.
A PC isn't a power distribution device.
You got two things right:
The NEC (and related fire codes) don't apply to supply cords of appliances in circumstances such as OP's PDU.
A PDU is *not* an appliance.
The modification cancels the UL certification. If you have an external requirement to use only UL certified components then you can't make any modifications no matter how obviously safe they are.
UL doesn't "certify" items. It "lists" them. It does so *specifically on behalf of* fire insurors.
By the way, you either don't have that requirement or you're breaking it. Your custom network cables are not UL certified.
Network cables don't carry power. Generally, Bill, you're one of the Smart People here. But what Lamar says accords with my (limited) formal electrical training, and what you say does not. Cheers, -- jra -- Jay R. Ashworth Baylink jra@baylink.com Designer The Things I Think RFC 2100 Ashworth & Associates http://www.bcp38.info 2000 Land Rover DII St Petersburg FL USA BCP38: Ask For It By Name! +1 727 647 1274