[secutanudu]

I had an outdoor lamppost stop working on me a while back. I finally decided to dig up the wire, which was installed by a previous owner. I bought a volt sensor and I think I found the part of the wire where the current breaks, meaning the volt sensor stopped beeping when i get to a particular point in the buried wire. The wire is not in conduit.

Now, what is the best way to fix this? Do I cut the few inches in question out of the wire, then reattach the two ends with direct-burial waterproof wire nuts? Should I enclose this in a junction box?

I really wish the wire was in conduit, as it probably would still be working. Is it necessary to dig up the entire thing and put it in conduit? It is heavy duty wire, and on the side it says "Sunlight resistant 600v". I am not certain if it is rated for direct burial, but it seems pretty thick.

Thanks!

 

[kbsparky]

Sounds like type UF wire to me with the "sunlight resistant" markings on it.

That means it is suitable for direct burial.

What kind of "volt sensor" are you using? Does the wire show any visible signs of damage where you believe it is broken?

 

[secutanudu]

It is a sensor I hold up to the wire, and it beeps if it detects a current. THere is a rip in the insulation of the wire in the spot where the sensor stops detecting current, so It appears I found the break in the wire.

 

[Ultrarunner2017]

There are splice kits made for splicing direct-burial cable. I think that your local Home Depot will have it.
You may need to make two splices, adding in a short length of cable (make sure it's UF and the same or larger gauge as what is there). You would then need two splice kits.

The voltage sensor sounds like what my Zircon stud finder has. It will detect an ac field around a wire. I suppose the one the OP is using is specifically designed for that purpose though.

FW

 

[secutanudu]

Yeah, it was a $10 device to detect the current.

I bought some direct burial waterproof wire nuts to make the connection. I didn't see (or look for, since I am just reading this) a splice kit...so I figured I'd need 6 wire nuts, 3 on each side (hot, neutral, ground).

I added some low-grade non-UL rated wire as a test, with normal wire nuts on each side. this fixed that segment of the wire (the volt sensor detected current on both sides of the splice), but the light still doesn't work. It must be ripped in more than one place. I've decided to just bite the bullet and rip up the wole thing, and lay new underground-rated wire in conduit.

Some questions on the proper and safe way to do this

Do I just buy PVC conduit and bury it with the wire inside, or is metal conduit better?

The old wire was about a foot deep, maybe 10", is that a good depth?

Can I leave the old wire in the ground, assuming it is not connected at either end, or is there a reason to take it out?

The current wire comes through the foundation and plugs right into an outlet. I planned to just leave it plugged in all the time and used a dusk-to-dawn light sensor at the socket. Any reason why I should add a switch, or just replace that outlet with a switch?

Any other suggestions?

Thanks again.

 

[Ultrarunner2017]

Good decision. Besides, I think you would need more than just wirenuts. The wires themselves have to be protected from the soil, so some sort of sleeving must be used over the entire splice.

NEC 2005, 300.5 says the following regarding depth of the cable:

Direct Burial Cable or conductors: 24"
Rigid Metal Conduit or Intermediate Metal Conduit: 6"
Residential Branch Circuits rated 120V or less with GFCI protection and maximum overcurrent protection of 20A: 12"

Running rigid metal conduit would probably be the easiest method, as it requires only 6" trench. Digging is hard work.
Of course, you need to make sure your conduit is sealed at any joints.

If you go with conduit, you don't need UF cable. You can just use THHN wires, but you will need to run three wires. Hot, Neutral, and Ground. Make sure the ground wire is bonded to the lamp post, and to the ground system at the source inside.
Where the conduit comes up into the lamp it must be protected so the wires are never exposed to soil or weather.

I don't think it matters whether you use a plug to connect to the receptacle or direct wire.
If you use a plug, it is going to have to be a heavy duty w ground, since the minimum wire size you can use is #14, and then you must use a 15A or smaller breaker.
IMO, it's going to be a PITA to connect THHN wires directly to a plug. They are not very flexible.
If you want, you could use a junction box, then go into a length of #14 SJ cord, but if you're going to use another J-box, then you might as well just run the conduit directly into a box and install a receptacle there.
You could use a switch, if you want alternative means of turning the light off.

Another idea would be to use a timer instead of the photo sensor in the lamp. Install an in-wall timer into the box where the lamp wiring connects to the indoor wiring.

Hope this helps

FW

 

[secutanudu]

The wirenuts i was planning to use were waterproof...they were filled with a gel that hardens when you use them, but anyway...

Thanks for all the info. A few more follow-up questions.

1. What about rigid PVC conduit? Easy to put together, cheap, light....is that still 6" depth?

2. The outlet that was being used for the lamp is not a GFCI outlet...I assume I should put one of those in instead?

3. Ground wire....it should be wrapped around a scre connected to the lamppost, and then wired to the ground on the fixture?

4. What's the best way to protect the wire as it exits the conduit and enters the lamp? Would just running UF cable through the conduit solve this problem?

5. I'm not familiar with different types of wire....the current wire is #12 Underground rated cable, which is attached to a plug. I guess it does make sense to get rid of the current outlet, replace it with a switch on a J-box, and route the THHN wires right into it. If those wires are too rigid to get around the switch, I can put some wire nuts and connect it to some of that #14 cord you mentioned, then to the switch. Is that what you meant?

I did think about using a timer, but the photo sensor makes so much more sense to me since I never have to adjust it for change of sunset/sunrise or daylight savings.


I think that's it, for now. I'll probably have more questions, but I am getting pretty clear on this. Thanks so much for the advice.

 

[jbberns]

Good decision. Besides, I think you would need more than just wirenuts. The wires themselves have to be protected from the soil, so some sort of sleeving must be used over the entire splice.

NEC 2005, 300.5 says the following regarding depth of the cable:

Direct Burial Cable or conductors: 24"
Rigid Metal Conduit or Intermediate Metal Conduit: 6"
Residential Branch Circuits rated 120V or less with GFCI protection and maximum overcurrent protection of 20A: 12"

Running rigid metal conduit would probably be the easiest method, as it requires only 6" trench. Digging is hard work.
Of course, you need to make sure your conduit is sealed at any joints.

If you go with conduit, you don't need UF cable. You can just use THHN wires, but you will need to run three wires. Hot, Neutral, and Ground. Make sure the ground wire is bonded to the lamp post, and to the ground system at the source inside.
Where the conduit comes up into the lamp it must be protected so the wires are never exposed to soil or weather.
FW

So do you just go by the code where you feel like it? A sleeve of conduit acts as a juction box? Direct burial cable has to be 24" deep but rigid is 6". How do you make the trasition from 24 to 6?
I had to fix a cable underground going to a pool pump a month ago. I had them dig a new trench and I ran a new cable. Save you from having to dig it up in a few years because it went bad. Just go ahead and do it right.

 

[secutanudu]

So do you just go by the code where you feel like it? A sleeve of conduit acts as a juction box? Direct burial cable has to be 24" deep but rigid is 6". How do you make the trasition from 24 to 6?
I had to fix a cable underground going to a pool pump a month ago. I had them dig a new trench and I ran a new cable. Save you from having to dig it up in a few years because it went bad. Just go ahead and do it right.

I'm not quite sure what you're suggesting here...

 

[jbberns]

I'm not quite sure what you're suggesting here...

You are what we call a slop artist. You follow the code on a few things but on most of it you go against the code.

Nec 90.1 (C) Intention. This Code is not intended as a design specification or an instruction manual for untrained persons.

You don't sound like you have much training!

 

[secutanudu]

I do not have any training, which is why I am posting my questions here. I am just a little confused with your response above. I did not make any references to code, I merely asked some questions.

I have no problem with criticism, as I like to know when I am doing things incorrectly, but I think we should check our name-calling at the playground.

 

[jbberns]

I'm not quite sure what you're suggesting here...

Sorry, I was referring to ke2kb. I understand that you were just looking help.

 

[Code05]

Okay lets start at the beginning. You have a post light wired with 12 UF cable plugged into an outlet, correct?

 

[Ultrarunner2017]

So do you just go by the code where you feel like it? A sleeve of conduit acts as a juction box? Direct burial cable has to be 24" deep but rigid is 6". How do you make the trasition from 24 to 6?
I had to fix a cable underground going to a pool pump a month ago. I had them dig a new trench and I ran a new cable. Save you from having to dig it up in a few years because it went bad. Just go ahead and do it right.

I'm not sure what you're criticizing me for here.
I only stated the code because the OP was asking for advice on how to bury a cable.
Code states different depths for different types of conduit/cable. The code is based on safety. A rigid metal conduit is much less likely to be damaged by a shovel, etc compared to a NM UF type cable. That is the reason for the varying depth requirements.
I was suggesting that the OP go with the RMC over direct-burial NM because digging a 24" trench is a lot more difficult that digging a 6" one.

I can't see how you are accusing me of going with code "when I feel like it". I always follow code, but sometimes may be a little confused as to which section of the code my application applies to, and will rectify this before I start a job.
I think you are jumpint to errant conclusions here. You think you can read my mind, but you cannot. Perhaps I wasn't as clear in my post as I should have been, that's all.

What are you talking about "a sleeve of conduit"?
Who said anything about just a sleeve? I think you may be gettinc confused with what I said about sleeving over the buried splice, and a whole new installation using conduit.

I thought I was being helpful, since I do have a copy of the 2005 (and an un-searchable PDF of the 2008) codes.

FW

 

[secutanudu]

Okay lets start at the beginning. You have a post light wired with 12 UF cable plugged into an outlet, correct?

Correct, and I want to rewire the whole thing in conduit. My original plan was to just use 12UF cable inside PVC conduit, that way the wire is protected if I need to exit the conduit to enter the lamp. I may try and run the conduit right into the post if I can.

 

[Ultrarunner2017]

The wirenuts i was planning to use were waterproof...they were filled with a gel that hardens when you use them, but anyway...

Thanks for all the info. A few more follow-up questions.

1. What about rigid PVC conduit? Easy to put together, cheap, light....is that still 6" depth?

2. The outlet that was being used for the lamp is not a GFCI outlet...I assume I should put one of those in instead?

3. Ground wire....it should be wrapped around a scre connected to the lamppost, and then wired to the ground on the fixture?

4. What's the best way to protect the wire as it exits the conduit and enters the lamp? Would just running UF cable through the conduit solve this problem?

5. I'm not familiar with different types of wire....the current wire is #12 Underground rated cable, which is attached to a plug. I guess it does make sense to get rid of the current outlet, replace it with a switch on a J-box, and route the THHN wires right into it. If those wires are too rigid to get around the switch, I can put some wire nuts and connect it to some of that #14 cord you mentioned, then to the switch. Is that what you meant?

I did think about using a timer, but the photo sensor makes so much more sense to me since I never have to adjust it for change of sunset/sunrise or daylight savings.


I think that's it, for now. I'll probably have more questions, but I am getting pretty clear on this. Thanks so much for the advice.

I was only quoting code because I thought it would be helpful, and rather than just making a statement, since I have a copy of the 2005 code I looked it up.
As far as type of conduit, the particular code I quoted made mention only of Rigid Metal Conduit.
I will look further if it will be of any help to you. You can also DL a copy of the current code for your locality on the web. That's where I got mine. Free, and searchable.

You are not required to have this circuit protected by a GFCI, unless there is a receptacle outdoors.
The only reason I stated the GFCI is that code allows type NM (UF) cable to be buried with less cover if it is GFCI protected and on 20A or lower breaker.

As for the wire-nuts you are talking about;
My point was that I believe the entire splice, including wire nuts, exposed wire should be covered with a sleeve that will protect it from the soil.
Perhaps the wire nuts alone are OK for outdoor wiring that is not buried, but I cannot imagine just allowing a buried splice with the outer jacket missing, and wires just buried directly with wire nuts, whether the nuts are approved for the purpose or not.
The splice kit I was referring to consists of wire nuts plus heat-shrinkable tubing which is itself rated for direct burial.

This splice type is however NOT permitted inside walls, ceilings, etc. In that case you would need a junction box.
The difference being that heat generated by the underground splice will not likely result in a fire, just loss of voltage, where in the walls, fire is much more likely.

I hope that I have not completely confused you. My intentions in this and every other forum I belong to are always based on attempting to help, not to create confusion or disagreeance.

FW

 

[Code05]

I thought I was being helpful, since I do have a copy of the 2005 (and an un-searchable PDF of the 2008) codes.

FW

Forget him, you are being helpful. Two things though, the wire needs to be THWN or dual rated for both and the OP has to hard wire or transition to SJ. UF/ NM/Romex is not listed for plugs to my knowledge.

 

[secutanudu]

First of all, KE2KB, thanks very much for all of the help and advice you are offering. I know that you are not trying to create confusion or disagreence.

That being said, I will also verify this with my town building dept. before i proceed.

If it is all the same, I will just use undeground rated wire within the conduit. It is not that expensive and if it does somehow come in contact with soil (though I will try to avoid it) then at least it is protected. Does this make sense?

You are not completely confusing me, I am just unfamiliar with all the acronyms and abbreviations when referring to different wire types.

My plan is to just replace the outlet that to which the lamp is wired with a GFCI outlet just to be safe, as it can't hurt (unless I forget to turn off the electricity first )

My basic plan at this point is to do this:

• Use PVC (if i can) or metal (if i must) conduit with underground-rated wire inside
• Dig a new trench as deep as I am required to (I will call my town for this info about each type of rigid conduit)
• Attach a plug to the end of the wire that enters the basement (like it is now)
• Replace the current receptacle with a GFCI one
• Attach the fixture to the underground wiring with waterproof wire nuts inside the post
• Attach a photo sensor and bulb at the fixture
• Post my success story here on the forums and thank everyone for their input
• Lay on the couch and watch tv

Anything about this seem unsafe or obviously wrong?

 

[Code05]

My basic plan at this point is to do this:

• Use PVC (if i can) or metal (if i must) conduit with underground-rated wire inside

PVC is fine.

• Dig a new trench as deep as I am required to (I will call my town for this info about each type of rigid conduit)

12" per 300.5 column 4 for residential GFCI 20 Amp circuit or 6" if Metal rigid

• Attach a plug to the end of the wire that enters the basement (like it is now)

No, plug is not listed for that cable. Transition to SJ or hardwire.

• Replace the current receptacle with a GFCI one

Good idea.

• Attach the fixture to the underground wiring with waterproof wire nuts inside the post

Regular is fine, but if it makes you happy.

• Attach a photo sensor and bulb at the fixture

Common installation.

• Post my success story here on the forums and thank everyone for their input
• Lay on the couch and watch tv

Anything about this seem unsafe or obviously wrong?

Hope this helps.

 

[secutanudu]

Hope this helps.

It does, thanks.

So I could run the underground wire into the basement, then to a switch, then to a GFCI outet, and eliminate the plug, right?