UV protection for SPT cord

[LORi P]

I am trying to decide what to use for extension cords. At first I was going to use all regular cords. Now I am thinking of making my own with SPT-1 or 2 wire. One of the concerns I have about using SPT wire is the UV deterioration of the SPT insulation.

Making SPT cords looks like it would be cheaper in many cases, but it may not be it it only holds up for a season or two.

I'd like to hear from people on the forum (whose cords are not covered with snow all the time) what experience they have had using the following:
1) SPT wire with no UV protection
2) Weather-X Cord cord that has UV inhibitor
3) SPT sprayed with Krylon UV spray

I'd especially like to hear from people who have used cords for multiple years with not problems. I've seen several posts from people who have reported their experience using UV protected cords for one season with no visible damage or problems. But I'd really like to know a little more about how they hold up for multiple years.

Is Weather-X cord really worth the extra money?
Does Krylon UV spray really help?
How much longer do cords with UV protection last compared to cords with no UV protection?
Are some colors of insulation naturally more UV-resistant than others (in one of the threads, I think someone mentioned that black might be best).

If anyone has used both UV protected and non-UV protected cords for multiple years, I'd love to hear how they compare.

Thanks!
LORi

[Rick Childers]

I am using the SPT with no UV protection, and very little snow. I have a yard grid wired up with them, and have been using it for three years now, going on four. They are still going strong, but maybe I have just been lucky.

[Steven]

I live in sunny California, and I leave the SPT cord to my roof lights up all year. So far, no problems!

[Guest guest]

I bought SPT-3 from CDI, so I'm covered, theoretically at least.

That said, even with living in FL, for cords that are outdoors for maybe 60 days beween November and January, I'm not sweating UV protection.

My vote would be option 1....

(Plus, trying to apply SPF-40 to a few thousand feet of cord takes so danged long, and makes such a mess..:shock:)

[Surfing4Dough]

Considering that we use our Xmas display cords for about 2 months, the amount of UV exposure is short. I have had some indoor cords (non-uv protected) I have used outside in the display for years (4-5) and SPT1 two years, and they don't seem any different from day one. I have no reason to believe they won't last 10 years. Other considerations, UV exposure during Xmas season is nearly zilch compared to summer (see below). A lot of my cords are under snow either way (great insulation), but many are not. Considering how inexpensive indoor extension cords are ($0.69-$2 depending on length), and how convenient their short lengths are, I am willing sacrifice that it may not last as long, considering I believe they are definitely going to live well beyond their cost. At best, a short outdoor cord costs 3-4 times as much as an indoor cord, and longer SPT runs are probably about half the price of outdoor extension cords. To earn its value, it is going to have to survive more than 2-4 times longer than an indoor/SPT cord--it very well may, but would have to wait 20-40 years to determine that. By that time, I hope we have wireless electricity anyway! :P

Difference in UV from December to June.




Note, UV index has nothing to do with temp. In the winter, the sun is hitting the northern hemisphere at a much greater angle so therefore the UV rays are blocked a lot more by the atmosphere, which is why the UV index is much lower that time of year (whereas in the summer the rays hit more directly on). See maps above for summer/winter comparison of the UV index for your area. UV index in Florida during the winter is still extremely low. That is why Floridians may have noticed that you are much more likely to get sunburn on a 80 degree day in the summer compared to a 80 degree day in the winter.

[gizmomkr]

Im onboard with Surfing4Dough.

The exposure is quite low. UV hitting a wire is not instant death to the cord. UV helps to break down the coating of the wire (as does heat) and over time causes it to become brittle.

The insulation will start to crack, break, and eventually crumble and fall off the wire.

I am using plain old spt1 with no UV proteciton. My cords have done fine for 3 years

I used to install wifi networks in outdoor locations, and over the years I saw miles of cable that sat on roof tops in direct sun all over the united states. UV protection does help, but it really is not a factor for cord thats only used seasonally. The stuff I saw on roof tops was left year round, and still took several years before it started to break down.

[-klb-]

Also, most black pigments are pretty good uv inhibitors by nature. I have a bunch of black SPT-2 that has gone through 4 seasons. Some of it has repeatedly sat in the back yard until I had to deal with it to mow the yard. I've also got a few cords that have been out for all four years, year round. Those few, you can see a little evidence of sun damage, but are still serviceable. The rest, all I see so far is light damage from scraping agains stuff in tear down. That light damage is robably the biggest reason I use spt2, not 1. More thickness to absorb light damage.

[CaptainCook]

I have over 500 SPT-2 cords that have been outside the majority of the time and this will be my 6th year with them. We live in Tampa, Florida and get a lot of UV during our summers. The only SPT damage I have is a slight discoloration in some of the brown cords. No physical hardening or cracking that I can tell. (and I am an Electrical Engineer by day, LOR by night)

I have a few older, specialized SPT-1 cords with vampire sockets that I have been using for 15-20 years and they are not quite as flexible as they used to be.

What the sun has damaged are some of the Tie Wraps! I have a four member Snowman & family from two years ago that has had about four months of winter UV exposure. You can't even touch the display without the tie wraps snapping. The ties are visibly discolored - slightly yellow - and we need to replace every one of them in order to move the displays this year. The ties were 4" ones that I purchased at Big Lots for something like $5 for 1,000. I didn't even think of the UV factor when purchasing them. All of my other ties are purchased in bulk from an electrical supply house, Harbor Freight or Home Depot and I have no problems with any of them.

With the amount of work everyone does with tie wraps, don't overlook the UV factor with them.