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15 amp vs 20 amp difference?

Been wondering about this for a while, some power conditioners (Shunyata in particular) and other equipment spec. to use a 20 amp power cord. What is the physical difference between the two? Would the plugs for iec and male input be different and not fit into the regular outlets (ie like the Oyaide GXS or PS Audio Ultimate or do they require a different type specifically just for 20 amp usage? I do realize the amp rating (that they'd draw) between the two would be different. Your help would help to further edudate me, Thanks.
rsjm80
nikturner920
144 posts
 
Seems to be common on the Shunyata products to use a 20amp IEC and the use a 15A AC plug with just the vertical plugs on the other end.

Just make sure that the cable you want to use is rated for 20A, not that you would usually ever draw that much current.
rodman99999
3,557 posts
 
I've never actually seen a 20A audio power cord with a true 20A plug. I just recently bought a 20A ZU Mother, and it had a 15A Wattgate plug.
jea48
2,944 posts
 
Shunyata Research equipment is UL/CSA Listed. Beings they use 20 amp receptacles they have to use a 20 amp IEC male connector to get the UL seal of approval.

For some reason a power cord with a 20 amp IEC connector and a 15 amp plug is ok with UL..... That one doesn't make any since to me. By allowing the configuration it is not idiot proof. Nothing prevents a user from plugging loads designed for a 20 amp branch circuit into a 15 amp branch circuit.....
Jim
inline_phil
11 posts
 
The issue lies in the wiring in the walls. The NEC specifies that the temperature of a wire cannot exceed a certain threshold when the maximum current is continuously used. This is specified to prevent electrical fires occuring inside of your walls from an overheated wire. So the breaker is then matched to the wire as are the outlets (here a 15A circuit). For this reason, changing the outlet to a 20A is risky without also changing the wiring from the breaker box to that outlet.
jea48
2,944 posts
 
For this reason, changing the outlet to a 20A is risky without also changing the wiring from the breaker box to that outlet.
Inline_phil
And that is why NEC says a 20 amp receptacle shall not be installed on a 15 amp branch circuit.....

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