Trench and conduit advice

[Wv lew]

It’s been a while Since I rand conduit, so let me pick your brains and thanks in advance;

1- anyone have an easy affective way to dig. A trench, other than shovel or trencher or backhoe?

2 I have lots of fire sprinkler 1” pvc I think I’m gonna use, as far as I can tell it’s the same as cpvc conduit. Thoughts? Also easiest way to pop into combiner box, inverter and from the outside to inside through 2x4 wall? Thanks.

 

[B-Mod]

Using "other pipe" as in not electrical pvc violates the electrical code if that matters. There are many ways to make a trench or install pipe. There is a cable plow to put wire underground. Other ways are using a plow, there is a small plow the is shaped like a v to make a trench.

 

[DougfromdaUP]

Yes, you can hire someone to bore it.

The proper tools really help. Buy a drain spade and a trenching shovel. I string a line, and take about one inch bites at a time with the drain spade just touching the line on one side. That will get you a straight narrow trench about 18” deep. Then put one knee on the ground, the other foot behind you in the trench, and use the trenching shovel to go deep enough to get your conduit where you need it.
I’m old, and I did 120 feet in one day through moderately hard soil for my array.
You will probably need a bar and a hammer for rocks,too.

I wouldn’t mess with anything but conduit.

 

[webbbn]

Arizona caliche just laughs at you if you try to dig it with a shovel. Here I would just rent a gas trencher. It's still not easy, but it's better than swinging a pickaxe.

The last time I dug some trench for landscaping pipe I used a gas tiller with a narrow blade configuration. The constant vibration in my hands gave me trigger finger for days, so I don't do that anymore.

 

[SolarSamAK]

I just ran a bunch of trenches. My local Home Depot rents a trencher for 69 USD for 4 hours. I used EMT pipe. 3/4 inch and ran four 10 gauge copper wires through them using a wire snake every 10 to 20 feet before compression coupling for a water tight seal. Use lube to help guide the wires. Limit your 90 degree turns or use a 90 degree pull through elbow. EMT code in my state is only 6 inches deep with fewer than three 90 angles without a pull through. Regardless I set the trencher to 8 inches. Do not want any issues as I am grid tied. Trencher is worth it. Saves time, effort and your back. Plus it was affordable at 69 USD. The PVC option while cheaper than EMT has to be 18 inches deep in my state, way too much work for me. Home Depot did charge me an extra 100 dollars for excessive cleaning. See the picture, I was robbed.
All products can be purchased at Home Depot, Lowes or any big box store. This entire project done by two men in late 40s took about 6 to 8 hours.

I ran about 60 to 80 feet from a solar shed project to my Sol Ark. Then a spare line to my kids playground probably 50 to 60 feet. Possible future solar expansion once they out grow the playground.

Let me know if I can answer any questions.

 

[DIYrich]

I just ran a bunch of trenches. My local Home Depot rents a trencher for 69 USD for 4 hours. I used EMT pipe. 3/4 inch and ran four 10 gauge copper wires through them using a wire snake every 10 to 20 feet before compression coupling for a water tight seal. Use lube to help guide the wires. Limit your 90 degree turns or use a 90 degree pull through elbow. EMT code in my state is only 6 inches deep with fewer than three 90 angles without a pull through. Regardless I set the trencher to 8 inches. Do not want any issues as I am grid tied. Trencher is worth it. Saves time, effort and your back. Plus it was affordable at 69 USD. The PVC option while cheaper than EMT has to be 18 inches deep in my state, way too much work for me. Home Depot did charge me an extra 100 dollars for excessive cleaning. See the picture, I was robbed.
All products can be purchased at Home Depot, Lowes or any big box store. This entire project done by two men in late 40s took about 6 to 8 hours.

I ran about 60 to 80 feet from a solar shed project to my Sol Ark. Then a spare line to my kids playground probably 50 to 60 feet. Possible future solar expansion once they out grow the playground.

Let me know if I can answer any questions.

I believe buried conduit requires galvanized RMC or IMC, and not EMT. If you go 24 inches deep, I suppose the EMT would be no worse than unprotected cable.

 

[Danke]

I believe buried conduit requires galvanized RMC or IMC, and not EMT. If you go 24 inches deep, I suppose the EMT would be no worse than unprotected cable.

Or you can use schedule 40 PVC for direct burial. “Schedule 40 rigid PVC conduit, elbows, that are specifically marked for underground use are suitable for use underground only by direct burial or encasement in concrete.”

Schedule 80 PVC rigid is often required above ground.

EMT is not meant for in ground (I believe it can corrode).

 

[Wv lew]

Using "other pipe" as in not electrical pvc violates the electrical code if that matters. There are many ways to make a trench or install pipe. There is a cable plow to put wire underground. Other ways are using a plow, there is a small plow the is shaped like a v to make a trench.

Yep, I’ve used one. I have non burial wire though so I need conduit. Thanks

 

[Wv lew]

Or you can use schedule 40 PVC for direct burial. “Schedule 40 rigid PVC conduit, elbows, that are specifically marked for underground use are suitable for use underground only by direct burial or encasement in concrete.”

Schedule 80 PVC rigid is often required above ground.

EMT is not met for in ground (I believe it can corrode).

That’s good to hear.

 

[SolarSamAK]

In the 2023 NEC, Section 358.10(A)(1) was revised to specifically allow EMT in direct burial applications with fittings identified for direct burial.

 

[B-Mod]

In the 2023 NEC, Section 358.10(A)(1) was revised to specifically allow EMT in direct burial applications with fittings identified for direct burial.

While this may be true, be sure to check state and local codes, because this can violate those codes. In Wisconsin you cannot direct bury EMT.

 

[CoolWill]

In the 2023 NEC, Section 358.10(A)(1) was revised to specifically allow EMT in direct burial applications with fittings identified for direct burial.

That's one of the dumbest changes they've made. Just because it can be done doesn't mean it should be done. Might as well just toss the wire in the ditch because that's basically what it will be when the EMT corrodes away in a few years.

 

[rhino]

1- anyone have an easy affective way to dig. A trench, other than shovel or trencher or backhoe?

How long is the trench going to be?

 

[timselectric]

EMT underground is a big no no.
You will be very lucky if it lasts 3 years.

 

[SolarSamAK]

Wow, not a lot of love to EMT. While not always the best option please keep in mind every situation is different. EMT that is zinc coated galvanized steel should make it about 50 to 75 years. All connections must be sealed if underground. Probably a longer life than the shed it is running to. My climate is such that I have a deep frost line. PVC at -20 F with lots of earth quakes also will not hold up well either. At those temps the PVC becomes a bit brittle. I am built into the side of a mountain s trenching down 18 inches is also not easy, lots of rock. I feel every project is like a mission. Define the goals of your mission and also check your local codes.
Here is a link that offers several solutions to running wires to a shed, shop or detached building. All options have a plus and minus in terms of benefits as well as cost. Also keep in mind weather conditions and weight loads. Are you going to be driving a tractor over this? Is the soil wet, what is the drainage, how cold does it get, what is the frost line depth, do you have frost heaves?

How to Install Underground Electrical Wiring (to a Garage, Shed, or Shop)

We cover all of the steps to show you how to install underground electrical wiring to a garage or shop including depth requirements and more.

www.protoolreviews.com

Hope this helps

 

[Q-Dog]

I drove a leftover piece of EMT into the ground about 18" to use as a stake and it collapsed from rust in less than a year. I wouldn't use it anywhere wet even if permitted.

 

[SolarSamAK]

I am sure PVC would have collapsed just as easily as the EMT though not due to rust.
Newer EMT that is zinc coated should last a while. Some good news, 6 to 8 months of the year there is no water or wet as everything is frozen where I am at. Then the thaw comes so a month of constant wet ground and frost heaves. EMT that is not sealed and left open will rust quickly. No doubt about it. Seal EMT if buried or used where exposed to rain or water.

 

[CoolWill]

Hey, it's fine. What's done is done. But as a matter of discussion, the zinc coating on EMT would have to be 6" thick to help it survive for any period in the dirt. Just vapor in the air in a horse barn will eat the conduit away in 5 years. Painting it really helps. But in dirt, you're dreaming if you think you can get 50 years out of it.

 

[rcrracer]

Trenching/narrow shovel. Hoe (whore if low budget enough) to rake the dirt back into the ditch. There is something in the NEC about burying conduit underneath concrete. Concrete needs to be a certain thickness and extend out on either side of the conduit minimum inches. Shallow ditch with concrete on top? Georgia buggy with tires and not tracks to move concrete...

 

[superchachi]

Depends on what kind of soil you have, how deep you want to have the finished trench to be. Other considerations are obstructions, how close you are to buildings (and other things you don't want to destroy), and how much actual work you want to do.

I have done a fair amount of this in our yard over the past 5 years. I have a tractor mounted backhoe with a 9" bucket. It is great...until you hit slabs of limestone and pull them out of the ground and make a 3to4' hole along the way. Then you also have mountains of spoils to deal with...so, you need plenty of space.

Chain driven trenchers, like the one above, are cool if you have pure dirt...otherwise you are in for a heck of a workout. You can get one that mounts on the front of a skid steer...much easier on the body, but you need the space to make sure you don't put a hole in the side of your house or any other item that you forget is behind you.

A rock saw, looks like something out of Mad Max, is the tool of choice around here for making trenches. We have limestone about 8" below the surface. Sometimes you get lucky and don't run into it for 2' or so...most of the time not. It will cut through anything...quickly. It makes nice, clean, deep trenches ready for use right away. The downside is, well, anything it touches will be destroyed.

Something else to consider is how deep and wide the trench is. If it is deeper than a foot or so, you may want to make sure it is wide enough to get your foot down into (width of your boot +). Working below your feet gets old...so, does trying to get your boot into a trench that is not wide enough to fit your boot into after you get tired of working below your feet.

To me, renting the right equipment or paying someone with the right equipment, is a good place to spend some of your budget if the trench is deep and long enough.