Extension Cords???

[bczygan]

I've noticed something peculiar about extension cords.

A number of cords out on the market that have 12 or even 10AWG wires, only have 15A ratings and the typical 15A plug.

I understand the reduction for longer cords, but this is also true on 50' cords.

Huh?

How do you take advantage of the full capability of the wire? Why the oversize?

Bill

 

[Strouty]

Could it be cheap wire and they have to derate it?

 

[sberry]

Its simply for voltage drop with heavy loading and motor starts. A 15 end passes 20 thru. The only thing a 20A plug does is specifically prevent it from being plugged in to a 15 recept. It can be uses as a lead cord for longer runs.

 

[bczygan]

Its simply for voltage drop with heavy loading and motor starts. A 15 end passes 20 thru. The only thing a 20A plug does is specifically prevent it from being plugged in to a 15 recept. It can be uses as a lead cord for longer runs.

I thought about the motor starts, but using as a lead cord is a great thought!

Does this mean the plugs on them are also really designed for higher amps?

Bill

 

[sberry]

No. It really isn't about amps but about plugs and recepts. I have went over this a couple times but,,,, here is a scenario. 20A are normally on dedicated circuits or to circuits dedicated to them. They are found mostly in institutions or even industrial. The idea is to keep specific equipment from being plugged in to them. I saw a common 10A vacuum with one on it, installed after the fact and the janitor had twisted it to fit a 15 anyway.
Say the science teacher or computer lab people set up an experiment, have it all running, office too,,, but then later the janitor comes along and uses the same circuit not knowing it may be partially loaded and out goes the breaker.
So,,, to prevent this they put in circuits for the cleaning equipment, ones it wont fuk everything or other stuff on to trip or have other parasitic load on, they put a long cord on the vac that reaches the recept they intend to be used for it. A 20A recept says,,,,,,, its ok to plug this stuff in here.
Big airless paint sprayer the same,,,, do you want to find out the circuit its just been plugged in to also has the office equipment on it?

 

[aandpdan]

I'm guessing economics...

Most people don't have 20 amp receptacles - NEMA 5-20P. To sell the same cord to more customers they use the standard 15 amp plug/receptacle - NEMA 5-15.

 

[slow]

Voltage drop, and if you need to connect 2 or 3 12/3 50 amp cords together, it is better than doing it with a thinner cord.

 

[theoldwizard1]

Portable cordage is usually downrated one step. Likely because of the additional voltage drop at the connector. If you are going to have an "overload" (high heat), it will be at the connector.

You would have a hard time finding an extension cord with a 5-20 plug. Of course, then you need a 5-20 receptacle to plug it into !

I always wish that 240V receptacles were more common, even 15A or 20A.

 

[sberry]

I like 120 where possible. everything portable I own will run 120. Yes, could rewire my table saw to 240 but it works fine at 120, I hardly use it. Great thing about new inverter welders. Soooooooooooooo much more convenient.

 

[sberry]

These cords are really for contractors with heavy saws and air comps. For running equipment unattended with multiple outlets where there was a possibility of overloads. A possibility where something could fault and run continuous.
I got more than most people do, I got a little bigger, some of it if they got 1 I got 2. Unless it is some really special project, a contractor deal usually I cant even remember the last time other than a couple welds I use a cord larger than a 16. Most of it today is cordless and running modest hand tools it isn't an issue, a guy can zing a 2/6 off with a circ with a 100 ft of 16 believe it or not,,,, ?
If I am setting up a sawing station to build a pole barn or a house then its a different matter.

 

[American Locomotive]

Portable cordage is usually downrated one step. Likely because of the additional voltage drop at the connector. If you are going to have an "overload" (high heat), it will be at the connector.

I always wish that 240V receptacles were more common, even 15A or 20A.

I noticed Lowes selling 10 AWG cords not too long ago. They were listed as "20A", and actually had a NEMA 5-20 plug on it. But the cord also came packaged with a little NEMA 5-15 to 5-20 adapter.

 

[kursplat]

i run my Lincoln mig 140 off a 50' 3-10w cord. the outlet is fed by #10cu with #8cu to the garage. also use it to feed other cords further out in the yard

 

[MDM]

For anyone looking for a deal on a 10 gauge, 100ft extension cord like this....

https://www.factoryauthorizedoutlet...foot-10-gauge-single-tap-extension-power-cord

 

[Ole Slewfoot]

i run my Lincoln mig 140 off a 50' 3-10w cord. the outlet is fed by #10cu with #8cu to the garage. also use it to feed other cords further out in the yard

You saved me typing the same post
When I get stuck using a lesser cord, it doesn't weld as well.

 

[sberry]

You would gain a volt or 2 between a 10 and 12, not much. 50 ft of 12 drops 3 or so on the welder wide open, 14 about 8.

 

[Blazinzuk]

In my semi jaded world view, the reason extension cords are slightly derated is because, and you know this happens all the time, someone is working with 3 splitters on 250 ft of cord and using way too much power but not enough to trip a breaker and something extremely flammable has been put on top of the cord.

Warning labels on ladders and the demise of any useful gas can come to mind

 

[theoldwizard1]

For anyone looking for a deal on a 10 gauge, 100ft extension cord like this....

https://www.factoryauthorizedoutlet...foot-10-gauge-single-tap-extension-power-cord

Good price, but it is SJTW cord which gets very stiff in cold weather and is NOT oil resistant.