Power cable question

Forums › Home Workshop DIY › Power cable question

Jeeves

301 posts

Ultimate Geek
+1 received by user: 90

#209133 14-Mar-2017 09:40

So on my travels, I've come across some C14 to C19 power leads, such as these:

http://www.rackpower.co.nz/products/52b17477c963bf89131ac02e

Given C14 is only rated to 10 amps, and C19 to 16 amps, doesn't that mean there is a high risk of overloading the cable? Surely this is unsafe/illegal?

One could argue that whatever the C14 is plugging into should have a 10amp breaker, but that often isn't the case. Think of any PDU that has multiple sockets that connect to say a single 20 amp upstream breaker. Whatever the C19 is plugging into is designed to draw up to 16 amps (Otherwise it wouldn't have a C20 socket!) and so could very much do so..

I'm just struggling to see how this is apparently perfectly legal/safe?

richms

29098 posts

Uber Geek
+1 received by user: 10209

Trusted

Lifetime subscriber

#1736195 14-Mar-2017 09:54

Any PC power supply over 1200 watts has one of those so needs that cable. Or the one with a 10a au/NZ plug on it. Not more than 10a on 230v so fine. Needs a 15a inlet for half strength voltage countries.

Richard rich.ms

tripper1000

1648 posts

Uber Geek
+1 received by user: 1176

#1736241 14-Mar-2017 11:10

Yeah, not an issue with regard to computers.

Over rated cable such as this doesn't cause more current to be draw, it simply means it can handle higher current should the connected appliance try and draw it.

If you manage to find a device that draws 15amps (say a large heating appliance - ?) this adaptor would enable you to plug it into a 10 amp max outlet, which will stress the 10amp wiring and cause the circuit breaker upstream on the building switch box to trip. It would therefore be imprudent to use this adaptor to hook-up an appliance that draws greater than 10 amps or 2400 watts.

As per above posters comment, in countries that use 110 volt mains (1/2 strength), a 1200 watt power supply draws 10.9 amps (at 1200 watts load), and therefore requires a 15amp lead and outlet. In NZ/AU/UK etc where we have 240 volt mains, a 1200watt power supply draws only 5 amps, so it is safe to use the linked 15-10amp adaptor cable and safe to use it on any appliance drawing 10amps/2400watts or less.

So to answer your question, yes, if you used it to connect up a device drawing greater than 2400watts@240volts, you are going to have trouble, however just because a device needs a C19 for use in the USA, doesn't mean it will overload 10amp wiring in NZ.

Edit: Re-read OP's question.