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Electrical Question - dumb one - but a good one

I am looking at an amp that has a 20 amp iec connection. I realize that my current power cord will not work - and I'm looking into have that '' retro-fitted '' with a 20 amp iec connection.....My question is ; '' the connection end at the wall - does the wiring, recepticle have to be changed because the amp end is now 20 amp iec, or does that stay the same and is okay as is '' ? Thank you.....
garebear

Showing 2 responses by almarg

almarg's avatar
almarg
9,670 posts
 
Also, judging by the wording of your question it's possible that the existing receptacle is already a 20A receptacle. 15A plugs can be plugged into 20A receptacles, but 20A plugs physically cannot be plugged into 15A receptacles.

A modern 20A receptacle looks like this. A 15A receptacle does not have the horizontal t-slot.

Re retrofitting the existing cord, obviously you have to make sure that the gauge of the cord is adequate to support the current drawn by the new amp. And if the gauge is not adequate to handle whatever the code requirement is for cords that have 20A connectors, it's probably not a good idea to use it because it might be used in a wrong application in the future.

Regards,
-- Al
almarg's avatar
almarg
9,670 posts
 
What?!

LOL. Good catch, Jim.

I found the following explanation here:

A standard outlet connects the AC ground wire to the back strap, and thus to the metal wiring box. The steel framework of a large building may be at a slightly different potential than the AC ground. If the wiring box is attached to the steel framework, the ground loop thus created may carry large currents and upset the operation of sensitive equipment plugged in to that outlet.

An isolated-ground outlet keeps the outlet grounds attached only to the AC ground wire from the local service panel, and breaks the ground loop. The building wiring has to have another ground for the wiring box. This configuration is not something that should benefit a typical home audio system.

I'm sure some people use them to provide a separate earth connection for the audio system's AC. This is illegal and can be very dangerous. If the system AC earth connection is physically separated from the main power earth connection, a nearby lightning strike can cause brief offset voltages of several thousand volts between the two earth connection points. This is caused by very large currents flowing laterally through the earth.

This spike can flash over and destroy your equipment. Worse, it can set the remains on fire.

Regards,
-- Al
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