DIY flat extension cord?

Have you seen the floor protectors ? Rubber pieces that are a few inches wide that the cord goes under ?

There are many variations of this.

To which I'd add the cheap version, Gaffer Tape.

(In a dire pinch, duck tape or even duct tape can be used ... )

RwP

here is a 10-foot (3 meter) version, and for outdoor use:

And, there are always these:

And for the well-heeled, needing flexibility:

We use a lot of the last for the mechanics. Good stuff!

Peter Wieck Melrose Park, PA

You don't state your location, but do note that at least in the USA, it is a violation of the electrical code to utilize an extension cord as a substitute for permanent wiring. So, if you are in the USA, and if this is a temporary thing, you'll be ok. But if are in the USA and you might plan to make this permanent you will fail a future electrical inspection should one occur.

Put a rug over it. Even magazines or those large padded shipping envelopes will work in a pinch.

I sometimes run temporary cabling above human traffic, but never anything carrying line power - There are permanent wall/cieling outlets in the lab.

For short periods, I've run flexible power cable on the floor, fixed into position at right angles to traffic by hazard tape.

For anything permanent, get the proper wiring done.

RL

Strange that such a statement would be in the code. Nothing is permanent.

This has to be one of the most insane pieces of advice ever given - excepting those from Jimmy Neutron. This approaches the quality of advice around using aluminum cans to cover holes in an automotive firewall.

Peter Wieck Melrose Park, PA

Have you read your local/national electrical code?

How about the warning tag on your last purchased extension cord?

RL

For short term use when I was displaying my book scanner at the Tulsa Maker Faire, a one day event, I plugged the extension cord into the provided in-the-floor outlet and then taped it to the floor. Gaffer tape is preferred, but duct tape or even masking tape will do.

Bill

National Electrical Code (NEC) does not allow extension cords in lieu of permanent wiring (NEC 400.8(1) - 2014 Version).

Article 400

Flexible Cords and Cables

400.8 Uses Not Permitted. Unless specifically permitted in 400.7, flexible cords and cables shall not be used for the following:

(1) As a substitute for the fixed wiring of a structure

(2) Where run through holes in walls, structural ceilings, suspended ceilings, dropped ceilings, or floors

(3) Where run through doorways, windows, or similar openings

(4) Where attached to building surfaces

Exception to (4): Flexible cord and cable shall be permitted to be attached to building surfaces in accordance with the provisions of 368.56(B)

(5) Where concealed by walls, floors, or ceilings or located above suspended or dropped ceilings

(6) Where installed in raceways, except as otherwise permitted in this Code

(7) Where subject to physical damage

Ok the second one refers to "fixed" and elaborates that use cases where it would be like the fixed wiring are not permitted, that is reasonable.

The first one probably should have read "in lieu of fixed wiring".

I have not purchased extension cords for several decades, but one that I have here does not mention that, it only mentions that it should only be used unrolled.

Of course I understand the use cases for extension cords, but I think the use of the word "permanent" is strange and vague, because nothing is ever permanent, and temporary solutions often last a long time (longer than some permanent ones!)

Yes, "in lieu of fixed wiring" would have used the wording from the NEC section.

Instead, it was using the "not easily removed" sub-definition of "permanant" (item 2(a) at the URL below):

Agreed. When putting an extension cord in a foot trafficed are you wrap it in oily rags, so the there's no friction to pinch the insulation. Then you cover it with a nylon rug or other insulating material.

There are speaker-cord solutions (very flat cable, suitable for under-rug use) but not recommended for AC line power. Another solution in utility areas is to screw a few hooks into the ceiling, and dangle the extension overhead.

The deluxe approach, of course, is to mount a floor receptacle, with suitable support and foot-traffic-capable cover. Search on "Hubbell floor receptacle" for examples.

What Power (Watts/VA), Current (Amps) is the "something pretty?" Exactly what distance to the wall outlet?

Does it have a wall wart adaptor? If it does, you could extend the output of that, with a different lighter cable - though you may lose power over an excessive length.

If you have walls that are plasterboard, fishing cables through them isn't too much work. You might have closer power on the other side of them.

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Adrian C