Last week i did some testing on my extension cords and thought i would share my findings. It is known that most cords fail under high load and at the ends. So here is how i decided to do the initial testing. I have a radiator heater that draws 1500 Watts on high which at my household voltage of 123V is 12.2A continuous. Run the heater on high for 5 mins through each cord and observe where the heat is generated and how much of it. I didnt go as far as to measure the temp with a thermometer but just touch and note if it is cool, warm , hot ect.
I tested 15 cords total
1) Bulldog Tough, 14 awg 25ft, OEM ends
1) MilSpec, 12 awg, 20ft OEM ends
1) US Wire Extreme, 50 ft , OEM ends
1) Voltec 16 awg, 25 feet extreme cold weather cord
3) Homemade with 16 awg and 14 awg computer cords with the end cut off and a duplex metal box attached to the end
1) Harbor Freight 12 awg 50 ft OEM ends
7) Various cheap orange cords 14 awg and 16 awg with OEM ends and some with aftermarket ends.
My rough findings are this.
The only three OEM cords that did not get warm or hot was the: US wire extreme, Milspec Direct, and the Prime Bulldog Tough. The 12 awg HF cord got barely warm but it is new, i have no doubt with minimal usage the ends would be fatigued and it too would heat up.
All the cheap orange cords got warm and a few got very hot. The worst was my 14 awg 50 footer that has been well used. In all cases the cords got hot at the ends and was usually both male and female ends ( I expected the female ends to fail more). The 16 awg cord, excluding the ends, did not get hot at all. After letting one of the 16 awg cords run for 20 mins you could start to feel a difference in the actual cord temp not just the ends. It was barely warmer than the cords laying on the floor with nothing plugged in.
The Voltec cord was fine on the male end but the female end was getting warm.
None of the cords that had aftermarket ends on them, male or female, got warm.
One of the worst cords which was the 14 awg 50 footer. This one I actually stopped the test after about two mins because the female end was getting very hot so there was no use in continuing. I cut the ends off and replaced with Leviton aftermarket ends and retested. No temp change observed. Proving that in this cord it was in fact the ends causing the temp increase.
I tested several cords since this experiment but they were all heavy gauge with aftermarket ends on them and none of them got warm at all. I didnt list them because one would expect 12 awg cords with good ends on them would not get warm and they dont.
I did this experiment to determine if it was necessary to run heavy gauge cords around the garage , less than 50 feet, or just use lighter cords with good ends. What I concluded is that if you use good quality ends, your probably in good shape even with some moderately heavy loads. For me , again < 50 ft , no need for 12 awg cords. A 14 awg cord with good ends will supply all the power i would use. If fact a 16 awg cord with good ends on it will cover 90 percent or more of what i need.
Outcome/ Summary
1) All cords that got warm or hot, did so at the ends.
2) I would not feel comfortable running much more than 12-13 amps, for any length of time, through a 16 awg cord regardless of the ends.
3) Be cautious when running large loads through cheap extension cords or ones with very used ends on them. Some of the cheaper ones that failed were not used all that much at all. The ends were not wore out. In fact the one was just about new so it leads you to believe that the ends are just not connected very well.
4) If i ever need to buy an extension cord, which i probably wont in my lifetime, I will most likely get SOOW 14/3 and put my own ends on it. This is definitely not the most cost effective though. Actually some SOOW 16/3 cords with nice ends would make great garage cords especially in very cold weather. Just be careful not to overload it. Many inexperienced people will see it and think it is thick so it must be heavy wire.
I realize everyone has different uses for cords and they may not be the same as mine. Some of my cords that failed and i cut the ends off of, you could probably use for another 20 years if your just running a drop light or something.
I just wanted to share my findings. Be careful guys when using old cords. The one that failed the worst, still got very warm even with the heater on medium which should only be 9 amps. For a 14 awg cord, it should have handled that easily.
I have a lot more detailed information in my notes about each test but dont want to type it all out here. If you have any specific questions, let me know.
I tested 15 cords total
1) Bulldog Tough, 14 awg 25ft, OEM ends
1) MilSpec, 12 awg, 20ft OEM ends
1) US Wire Extreme, 50 ft , OEM ends
1) Voltec 16 awg, 25 feet extreme cold weather cord
3) Homemade with 16 awg and 14 awg computer cords with the end cut off and a duplex metal box attached to the end
1) Harbor Freight 12 awg 50 ft OEM ends
7) Various cheap orange cords 14 awg and 16 awg with OEM ends and some with aftermarket ends.
My rough findings are this.
The only three OEM cords that did not get warm or hot was the: US wire extreme, Milspec Direct, and the Prime Bulldog Tough. The 12 awg HF cord got barely warm but it is new, i have no doubt with minimal usage the ends would be fatigued and it too would heat up.
All the cheap orange cords got warm and a few got very hot. The worst was my 14 awg 50 footer that has been well used. In all cases the cords got hot at the ends and was usually both male and female ends ( I expected the female ends to fail more). The 16 awg cord, excluding the ends, did not get hot at all. After letting one of the 16 awg cords run for 20 mins you could start to feel a difference in the actual cord temp not just the ends. It was barely warmer than the cords laying on the floor with nothing plugged in.
The Voltec cord was fine on the male end but the female end was getting warm.
None of the cords that had aftermarket ends on them, male or female, got warm.
One of the worst cords which was the 14 awg 50 footer. This one I actually stopped the test after about two mins because the female end was getting very hot so there was no use in continuing. I cut the ends off and replaced with Leviton aftermarket ends and retested. No temp change observed. Proving that in this cord it was in fact the ends causing the temp increase.
I tested several cords since this experiment but they were all heavy gauge with aftermarket ends on them and none of them got warm at all. I didnt list them because one would expect 12 awg cords with good ends on them would not get warm and they dont.
I did this experiment to determine if it was necessary to run heavy gauge cords around the garage , less than 50 feet, or just use lighter cords with good ends. What I concluded is that if you use good quality ends, your probably in good shape even with some moderately heavy loads. For me , again < 50 ft , no need for 12 awg cords. A 14 awg cord with good ends will supply all the power i would use. If fact a 16 awg cord with good ends on it will cover 90 percent or more of what i need.
Outcome/ Summary
1) All cords that got warm or hot, did so at the ends.
2) I would not feel comfortable running much more than 12-13 amps, for any length of time, through a 16 awg cord regardless of the ends.
3) Be cautious when running large loads through cheap extension cords or ones with very used ends on them. Some of the cheaper ones that failed were not used all that much at all. The ends were not wore out. In fact the one was just about new so it leads you to believe that the ends are just not connected very well.
4) If i ever need to buy an extension cord, which i probably wont in my lifetime, I will most likely get SOOW 14/3 and put my own ends on it. This is definitely not the most cost effective though. Actually some SOOW 16/3 cords with nice ends would make great garage cords especially in very cold weather. Just be careful not to overload it. Many inexperienced people will see it and think it is thick so it must be heavy wire.
I realize everyone has different uses for cords and they may not be the same as mine. Some of my cords that failed and i cut the ends off of, you could probably use for another 20 years if your just running a drop light or something.
I just wanted to share my findings. Be careful guys when using old cords. The one that failed the worst, still got very warm even with the heater on medium which should only be 9 amps. For a 14 awg cord, it should have handled that easily.
I have a lot more detailed information in my notes about each test but dont want to type it all out here. If you have any specific questions, let me know.
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