Another Vexing Extension Cord Question

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drawpoker
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Another Vexing Extension Cord Question

Post by drawpoker »

Thanks to fellow bogleheads earlier - I acquired the GFIC gizmo I needed for the outside outlet to plug in my corded electric mower this season. So no more worries about premature death by electrocution. :D

Next problem tho - My heavy-duty, 14 gauge 100 foot extension cord has developed peculiar habit of getting kinky in the remote end of the cord, last 20-25 feet of the 100 foot draw from the outlet to the mower connection. They look like little S-shape rolls, and the cord feels much stiffer in those little rolls than in the rest of the cord.
My mower is listed as 9 amps, and the Coleman Cord says it is good for "15-a for 50 feet" and then "13-a for 100 feet. I am assuming that means the cord will deliver 15 amps for the first half, then it drops to only 13 amps from 50 feet to the very end.
Reasonable enough, but I don't understand why the cord is acting like this when the most I am drawing with my mower is 9 amps. The manual says it is fine to use a 100 foot cord, but nothing longer.
The only thing I am guilty of - the cord did say "store indoors when not in use". For reasons no one is interested in, I have stored the cord for the past three winters in the trunk of my car, instead of inside my house. ( Towards the end of last year's mowing season is when the mysterious kinking started)
Could that (defying storage instructions) have in some way (maybe temperature swings) have damaged the cord?
Or Is it normal for outdoor extension cords to have wear and tear in this manner? I have carefully checked the entire length for cracks, holes, any signs of damage. Nothing. There has been no tripping of breaker either.
Is this anything to worry about? The mower seems to be running normally, but I don't want to do anything that might cause damage to it if this extension cord is going bad and should be replaced.
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BolderBoy
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Re: Another Vexing Extension Cord Question

Post by BolderBoy »

drawpoker wrote:My mower is listed as 9 amps, and the Coleman Cord says it is good for "15-a for 50 feet" and then "13-a for 100 feet. I am assuming that means the cord will deliver 15 amps for the first half, then it drops to only 13 amps from 50 feet to the very end.
How warm does the cord get at the end close to the mower, when the mower is operating?
PS241
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Re: Another Vexing Extension Cord Question

Post by PS241 »

Your extension cord is made up of 3 wires wrapped inside the plastic outer sheath. Could it just be due to your turns back and forth with the mower that the internal wires are getting an unusual twist?
Mudpuppy
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Re: Another Vexing Extension Cord Question

Post by Mudpuppy »

drawpoker wrote:Next problem tho - My heavy-duty, 14 gauge 100 foot extension cord has developed peculiar habit of getting kinky in the remote end of the cord, last 20-25 feet of the 100 foot draw from the outlet to the mower connection. They look like little S-shape rolls, and the cord feels much stiffer in those little rolls than in the rest of the cord.
This likely has to do with how you loop up the cord to store it. If you are just simply looping it up (e.g. wrapping it around your arm or a cord caddy) then you'll get kinks eventually. Do the S-shape rolls look a bit like what's in this picture of the wrong way of wrapping it? Picture: http://www.instructables.com/file/FR59OCXH1ERN65Y

If so, that means the cord has been affected by how it's been stored. Essentially, you're twisting the internal wires due to the way you're wrapping the cord up to store it. It's a pretty common mistake with all sorts of cords, but the twisting effect gets magnified by longer cords. I did the same thing to my first 100' extension cord for lawn equipment before discovering the proper way to store cords.

To get the fewest kinks and the longest life from any sort of cord, you should be utilizing the over-under technique to loop up cords. It does take a little bit longer to wrap up a 100' cord at first, but eventually I got the muscle memory for it. Here's a Youtube video demonstrating the over-under technique on an AV cable: https://www.youtube.com/watch?v=0yPcJD7RVuY
The Wizard
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Re: Another Vexing Extension Cord Question

Post by The Wizard »

100 foot cords are hard to deal with.
I find it easier to use two or three 50 foot cords instead, though usually for a leaf blower, since I have a gas mower.
And I always use top quality winter-flexible cords nowadays.

I've seen the problem OP mentions in one of my GF's old outdoor cords. I'm pretty sure the three wires inside the cord have twisted around somehow.

As for the ampacity of extension cords, that Coleman quote is baloney. 14 gauge extension cords can safely deliver 15 amps for thousands of feet without overheating the wire and causing a fire hazard.
The problem is, you get more Voltage Drop the longer the cord is, depending on how big the load is at the far end of the cord.
115 volts at the house can drop to 100 or 90 volts at the power tool, depending on cord length and gauge.
Too low voltage can damage the mower with heavy use.
They sometimes specify acceptable gauge/length combos, such as 14 ga for 50 feet, or 12 ga for 100 feet...
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drawpoker
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Re: Another Vexing Extension Cord Question

Post by drawpoker »

BolderBoy wrote: How warm does the cord get at the end close to the mower, when the mower is operating?
Not warm at all, and I know this because I frequently have to grab the cord to toss it out of the path when I change directions while mowing.
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drawpoker
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Re: Another Vexing Extension Cord Question

Post by drawpoker »

Mudpuppy wrote: This likely has to do with how you loop up the cord to store it. If you are just simply looping it up (e.g. wrapping it around your arm or a cord caddy) then you'll get kinks eventually. .... means the cord has been affected by how it's been stored. Essentially, you're twisting the internal wires due to the way you're wrapping the cord up to store it..... twisting effect gets magnified by longer cords. ....To get the fewest kinks and the longest life from any sort of cord, you should be utilizing the over-under technique... does take a little bit longer to wrap up a 100' cord at first, but eventually I got the muscle memory for it. Here's a Youtube video demonstrating the over-under technique on an AV cable: https://www.youtube.com/watch?v=0yPcJD7RVuY
That makes sense. But, unlike the guy in the video looping the lightweight cable, think my cord weighs around 18-20 lbs. :shock: What he makes look easy is NOT going to be easy for a woman to do (unless she is already a bodybuilding competitor :?: )

Thanks to all for the info.
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drawpoker
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Re: Another Vexing Extension Cord Question

Post by drawpoker »

The Wizard wrote:100 foot cords are hard to deal with.
I find it easier to use two or three 50 foot cords instead

Somewhere I read (maybe in the manual) do not use multiple extension cords.


...that Coleman quote is baloney. 14 gauge extension cords can safely deliver 15 amps for thousands of feet without overheating the wire and causing a fire hazard.
The problem is, you get more Voltage Drop the longer the cord is, depending on how big the load is at the far end of the cord.
115 volts at the house can drop to 100 or 90 volts at the power tool, depending on cord length and gauge.
Too low voltage can damage the mower with heavy use.

How do you define 'heavy use"? Running mower for more than 30 minutes at a time?

They sometimes specify acceptable gauge/length combos, such as 14 ga for 50 feet, or 12 ga for 100 feet...
It does. But it says 100 feet of 14 gauge is fine for any tools rated at 15 amps or less. My mower claims to be a 9-amp model.
Professor Emeritus
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Re: Another Vexing Extension Cord Question

Post by Professor Emeritus »

The Wizard wrote: As for the ampacity of extension cords, that Coleman quote is baloney. 14 gauge extension cords can safely deliver 15 amps for thousands of feet without overheating the wire and causing a fire hazard.
The problem is, you get more Voltage Drop the longer the cord is, depending on how big the load is at the far end of the cord.
115 volts at the house can drop to 100 or 90 volts at the power tool, depending on cord length and gauge.
Too low voltage can damage the mower with heavy use.
They sometimes specify acceptable gauge/length combos, such as 14 ga for 50 feet, or 12 ga for 100 feet...
Motor Loads are in watts not amps. as the voltage drops the amps increase.
That is why you use cords of larger capacity They have less voltage drop and they can handle larger loads
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Re: Another Vexing Extension Cord Question

Post by dbr »

drawpoker wrote:those little rolls than in the rest of the cord.
My mower is listed as 9 amps, and the Coleman Cord says it is good for "15-a for 50 feet" and then "13-a for 100 feet. I am assuming that means the cord will deliver 15 amps for the first half, then it drops to only 13 amps from 50 feet to the very end.
R
No, that means the cord is approved for a 15 amp load at a fifty foot length but only for a 13 amp load at a one hundred foot length. Amps are a rate of flow of electrical charge (also called a current) and are the same from one end of a circuit to another. The problem is that when charge flows down a conductor there is a drop in potential (also called voltage) continuously along the length.

Here is a calculator to use in rating cords: http://buyextensioncord.com/info_voltage_drop.shtml
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drawpoker
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Re: Another Vexing Extension Cord Question

Post by drawpoker »

dbr wrote:.... problem is that when charge flows down a conductor there is a drop in potential (also called voltage) continuously along the length.

Here is a calculator to use in rating cords: http://buyextensioncord.com/info_voltage_drop.shtml
Thanks, dbr, for the calculator.

I entered "copper" instead of aluminum (is that right?) Think I got the rest right, and the answer came back a drop of 5.6 volts, or 4.7 % voltage drop, at the end of the 100 foot line (circuit?)

4.7% isn't bad, is it? :?
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Bengineer
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Re: Another Vexing Extension Cord Question

Post by Bengineer »

Mudpuppy wrote:...To get the fewest kinks and the longest life from any sort of cord, you should be utilizing the over-under technique to loop up cords. It does take a little bit longer to wrap up a 100' cord at first, but eventually I got the muscle memory for it. Here's a Youtube video demonstrating the over-under technique on an AV cable: https://www.youtube.com/watch?v=0yPcJD7RVuY
Now that is a useful piece of information. Not only does the "wrap it up on your arm" technique twist the cable, but it also kinks up when you pay it out to use it. This also works for long air & water hoses. Thanks, Mudpuppy!
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Re: Another Vexing Extension Cord Question

Post by The Wizard »

drawpoker wrote:
dbr wrote:.... problem is that when charge flows down a conductor there is a drop in potential (also called voltage) continuously along the length.

Here is a calculator to use in rating cords: http://buyextensioncord.com/info_voltage_drop.shtml
Thanks, dbr, for the calculator.

I entered "copper" instead of aluminum (is that right?) Think I got the rest right, and the answer came back a drop of 5.6 volts, or 4.7 % voltage drop, at the end of the 100 foot line (circuit?)

4.7% isn't bad, is it? :?
Probably not, but we engineers are inclined to say that it depends entirely on the required voltage at the load under normal operating conditions.
Also, to be more precise, you might want to include the drop in the house wiring getting from the panel to the receptacle you're using.
Or just take an ad hoc approach: get a voltmeter and measure the voltage UNDER LOAD at the power tool (mower?).
Might have to pull the plug 1/8" out of ext cord receptacle to access the two blades.
Would be good to do this safely and report back...
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Re: Another Vexing Extension Cord Question

Post by Mudpuppy »

drawpoker wrote:
Mudpuppy wrote: This likely has to do with how you loop up the cord to store it. If you are just simply looping it up (e.g. wrapping it around your arm or a cord caddy) then you'll get kinks eventually. .... means the cord has been affected by how it's been stored. Essentially, you're twisting the internal wires due to the way you're wrapping the cord up to store it..... twisting effect gets magnified by longer cords. ....To get the fewest kinks and the longest life from any sort of cord, you should be utilizing the over-under technique... does take a little bit longer to wrap up a 100' cord at first, but eventually I got the muscle memory for it. Here's a Youtube video demonstrating the over-under technique on an AV cable: https://www.youtube.com/watch?v=0yPcJD7RVuY
That makes sense. But, unlike the guy in the video looping the lightweight cable, think my cord weighs around 18-20 lbs. :shock: What he makes look easy is NOT going to be easy for a woman to do (unless she is already a bodybuilding competitor :?: )

Thanks to all for the info.
I'm a woman. And it's not easy at first. Yeah, my arms got tired when I first started using the over-under technique on the 100' extension cord. I sometimes had to pause let my arms hang loose just to give the muscles a break. But the trick is to use big loops (my loops are at least twice in diameter as those in the videos) so there's fewer loops to have to gather up and to practice on shorter, lighter cords to get the muscle memory for the over-under technique so you can do it quickly.

Alternatively, you can just buy a new 100' cord when it starts to get horribly twisted up. There is a risk of a short or overheating when using a severely twisted extension cord, but it takes a few years to get to that point. So maybe buying a new one every few years is a viable work around.

Edit: Fix typo
dolphinsaremammals
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Re: Another Vexing Extension Cord Question

Post by dolphinsaremammals »

drawpoker wrote: That makes sense. But, unlike the guy in the video looping the lightweight cable, think my cord weighs around 18-20 lbs. :shock: What he makes look easy is NOT going to be easy for a woman to do (unless she is already a bodybuilding competitor :?: )
I have a couple of 50 foot heavy duty outside extension cords. I have inadvertently been looping them the correct way, and they're in fine shape, even though my Dad gave them to me thirty years ago. There's no way on the planet that the two cords together weigh 18-20 pounds. I'm too lazy to go get them and weigh them, but my guess is five pounds max total.

I just looked one up on Amazon, and a 100 feet 16 gauge exterior extension cord that looks a lot like mine has a shipping weight of 5.8 lbs.

You seem to make a lot of posts assuming women are feeble beings. If a 70+ year old not particularly active woman like myself can do this, I think it's highly likely you can do it.
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Re: Another Vexing Extension Cord Question

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Re: Another Vexing Extension Cord Question

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I removed a number of off-topic posts which got into a disagreement on physical strength capabilities of women.

The question has been answered, this thread will remain locked.
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