Electrical Wiring DOES Degrade with Time

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rrnut-2
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Re: Electrical Wiring DOES Degrade with Time

Post by rrnut-2 »

It is the type of wire. SO & SJ cords do not last very long with that type of insulation. The current that it carries really doesn't matter as long as it is within its rating. Most of the machinery that we build, we are not allowed to use that type of cord for that very reason as it goes away faster in the tropics.

Jim B
whateg0
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Re: Electrical Wiring DOES Degrade with Time

Post by whateg0 »

What is the best, in y'all's opinion, cord to use when wiring up a machine in a shop environment? I always thought some or sjoow we're good choices because they remain flexible and are pool resistant. But I too have seen it degrade faster than I expected
rrnut-2
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Re: Electrical Wiring DOES Degrade with Time

Post by rrnut-2 »

I use SJEOOW, TPE Rubber, MSHA Approved type of cords for our machinery. This seem to last longer than the EPDM Rubber cords.

But, it isn't because of longevity, it is because of the filler used between the cords. These cords use a pvc strand filler between the conductor instead of paper. My understanding is the paper gets eaten by bugs in some places in the world. Since we ship control systems all over the world, we have to worry about this kind of stuff.

Inside of the panels, we use mostly UL1015 wire.

Jim B
whateg0
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Re: Electrical Wiring DOES Degrade with Time

Post by whateg0 »

whateg0 wrote: Tue Dec 14, 2021 5:05 pm What is the best, in y'all's opinion, cord to use when wiring up a machine in a shop environment? I always thought some or sjoow we're good choices because they remain flexible and are pool resistant. But I too have seen it degrade faster than I expected
Ffs! I just reread my post. Stupid phone!

...soow or sjoow...

... Oil resistant...
Howard Gorin
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Re: Electrical Wiring DOES Degrade with Time

Post by Howard Gorin »

Pigmentation of the rubber can affect the life of rubber insulation. I have examples of SO wire where some insulation would fail under the rubber jacket. Other conductors were still like new. I have a very old, maybe ancient Mall Saw maybe sixty years old. The power cord is perfect. Maybe there are different grades of rubber.
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BadDog
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Re: Electrical Wiring DOES Degrade with Time

Post by BadDog »

I have a very low use example of the US made (pre-import) 20" Wilton VSG heavy duty drill press. I took it out of commission for a few months after noticing that the sheathing on the red wire had become brittle and very fragile. In a number of locations where there is no movement or flexing other than vibratory it was cracked completely through allowing the copper stranded conductor to be clearly seen in-situ. I replaced all the wiring, and when extracted, the red wire was completely junk from end to end. The only thing preventing substantial related damage was that the wire was well secured along it's length, and there was no point where the wire moves or flexes in use.
Russ
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