AC -> DC -> AC pond wiring - good idea or stupid?

[Sparky]

Now you’re on the right track! Yes, you can run waterline in the same ditch or sleeve under the driveway. Yes you will want access to the sleeve for future use. Since you have the option to later run more stuff, I would get yourself a roll of 12-2 UF cable and run two through there. You might want to up your sleeve to 3”. Make sure it’s schedule 80 pvc.

 

[poconojoe]

Just as a note: if you're still going with your original idea of tapping into that existing GFCI, you will be limited to that single existing circuit. What size wire is feeding it and what size circuit breaker? And most likely that GFCI is not the only load on that circuit. So, if you go this route, spare conductors, as suggested, although a good idea, will be useless.
So, what I'm getting at is feeding you new circuit(s) directly from your circuit breaker panel. This way it will be on a separate circuit dedicated strictly for your new pond. Also those suggested spares will be in your panel for future use.
Me personally.. I would run a PVC conduit throughout the whole run. I don't mean to put down anyone else's ideas, but I wouldn't use direct burial cable. A 3/4 conduit would allow you to run many individual conductors or at least have the option to add circuits in the future. If you use direct burial cable, you are permanently limited to what you bury. 3/4" PVC conduit and it's fittings are not very costly. You could mount a junction box on the outside of your house and can always tap into that for future use.
So, where is your electrical panel located in relation to the pond and driveway? Are there any spare spaces open for use in you panel?

 

[Sparky]

Poconojoe is correct about homerunnng to the panel. Conduit the whole way is always better. However, I was looking cost and the givens. Except for well systems and septic fields, the majority of outside wiring I do is SPL (source to pipe to load). Have to up here with frost heaves and rock EVERYWHERE. Ground looks pretty forgiving where you are.

 

[johnkim]

Hi popconojoe & Sparky,

Thanks. I dug 10 feet of trench of 18" depth today and found something interesting. The front yard has a 12VAC line already from the house. I didn't know how the line was buried until I dug it up today.

It appears to be buried by a 3.5" white PVC pipe running across the driveway. Measuring from the top of the pipe, the depth is about 15" below the ground. If we account for the 3.5" diameter of the pipe, it seems to be buried 18" deep which should be safe and meet the code

I have two options now:

1. connect the existing PVC pipe to a new conduit for the new section and bury the new conduit in the trench I dug. Feed 12/3 UF wire through this existing pipe. This will save me time from digging up the 20 feet paver driveway.

2. dig up the existing PVC pipe and run a new conduit. This will take more time


What should I do?

The trench is dug up on the grass area. Still need to dig up the driveway

Existing PVC pipe with 12VAC wire

PVC depth from top of the pipe is 15"

PVC diameter is 3.5"

Exit hole of the other side of the PVC

 

[Sparky]

Brilliant! Fantastic work. Use that pipe as a sleeve under the drive. Run your waterline through it or anything else since it’s exposed. Run two 12-2s as one could be used for a switch leg or traveler (3way) or spare just in case. That UF can just lay in the ground now that I see your ground exposed. You are golden. White pvc not so much but it’s not being used as a “raceway” just a sleeve. No need to replace. Your depth is fine. Now to get the end to a hot or the panel. Can you sketch me your house with the drive, sleeve, exterior boxes and panel location. You can do this! Legally and safely I might add.

 

[poconojoe]

Wow! So if I understand you correctly, there was an existing 3.5" PVC already running under the driveway. What a lucky break. Especially right where you started trenching. Dude, you need to buy a lottery ticket! As sparky said you can use this as a sleeve to run whatever you want. You can pass a UF cable, a conduit or a water line right through there.

 

[johnkim]

Brilliant! Fantastic work. Use that pipe as a sleeve under the drive. Run your waterline through it or anything else since it’s exposed. Run two 12-2s as one could be used for a switch leg or traveler (3way) or spare just in case. That UF can just lay in the ground now that I see your ground exposed. You are golden. White pvc not so much but it’s not being used as a “raceway” just a sleeve. No need to replace. Your depth is fine. Now to get the end to a hot or the panel. Can you sketch me your house with the drive, sleeve, exterior boxes and panel location. You can do this! Legally and safely I might add.

Thanks Sparky. I will create a drawing. I'm thinking just wiring to my existing outdoor GFCI socket to make the job simpler.

My other question is if I run waterhose in the same PVC sleeve as the UF wire and 12VAC wire, how do I set the exit point for each connection? Should I use a splitter manifold like this? One end will attach to a schedule 80 PVC above ground to the new GFCI pond socket. The other end will be for the water hose.

Should I run 12/2 or 12/3?

Lastly, since the PVC is just a sleeve, I should not have to worry if water gets in as long as my wires are UF?

 

[Sparky]

Thanks Sparky. I will create a drawing. I'm thinking just wiring to my existing outdoor GFCI socket to make the job simpler.

My other question is if I run waterhose in the same PVC sleeve as the UF wire and 12VAC wire, how do I set the exit point for each connection? Should I use a splitter manifold like this? One end will attach to a schedule 80 PVC above ground to the new GFCI pond socket. The other end will be for the water hose.

Should I run 12/2 or 12/3?

Lastly, since the PVC is just a sleeve, I should not have to worry if water gets in as long as my wires are UF?

-Pond High Volt: Shopping List- 1 single gang deep weatherproof box with 3/4” threaded knockouts, 1 weatherproof in-use cover (type where it closes with cord end inserted),2- 3/4” pvc male adapter, 1 stick 3/4” pvc schedule 80, 1 weather/tamper resistant GFI, 4- 3/4” rigid 2 hole straps and 12/2 if you haven’t got it and a 4x4 post (3 or 4’)

I gotta run but the above should be everything to complete the pump circuit. More later.

 

[johnkim]

-Pond High Volt: Shopping List- 1 single gang deep weatherproof box with 3/4” threaded knockouts, 1 weatherproof in-use cover (type where it closes with cord end inserted),2- 3/4” pvc male adapter, 1 stick 3/4” pvc schedule 80, 1 weather/tamper resistant GFI, 4- 3/4” rigid 2 hole straps and 12/2 if you haven’t got it and a 4x4 post (3 or 4’)

I gotta run but the above should be everything to complete the pump circuit. More later.

Thanks Sparky. How do I transition from the 3" PVC to 1" (or 3/4") PVC? I don't think such adapter exists.

 

[Sparky]

You don’t. Where do you invision having to do this? Again, think of the 3” just as a tunnel under the drive. The 3/4 is just to protect the UF as it leaves the ditch at the pump location and existing outlet location.

 

[johnkim]

Hi Sparky,

I'm thinking having the 3" pipe in the ditch then have a 90 degree elbow at the position of the receptacle. In this case, I assume I can just insert the 3/4 inch pipe on top of the 90 degree elbow and use dirt to secure it so it doesn't move around?

 

[Sparky]

I didn’t realize the 3” was being extended. What I would do is exit the elbow on top with a hole just big enough for the UF to slide through. Make sure to file the edges of the hole. Free run the UF to the post location and a straight sleeve of pipe to bring it into the box. Use duct seal (like a putty) to seal around the uf so dirt doesn’t get in there. (On top of elbow) Make sense? Also I always leave a service loop of about 2-3feet buried before going up the pipe. Comes in handy later trust me.

 

[johnkim]

I didn’t realize the 3” was being extended. What I would do is exit the elbow on top with a hole just big enough for the UF to slide through. Make sure to file the edges of the hole. Free run the UF to the post location and a straight sleeve of pipe to bring it into the box. Use duct seal (like a putty) to seal around the uf so dirt doesn’t get in there. (On top of elbow) Make sense? Also I always leave a service loop of about 2-3feet buried before going up the pipe. Comes in handy later trust me.

Hi Sparky,

Thanks for the tips. I ended up using 1/2 conduit. My GFCI box was 1/2 hole and didn't want to bother with reducer. it was a bit tight for the 12/2 UF wire. In retrospective, I should've used 3/4 and used reducer. I managed to installed the outlets and tested both GFCI outlets perform as per spec. I only need to bury the dirt now and secure the conduit to my brick wall. Thanks again for the great help! I'm super excited to start building my fountain since the power is taken care off. I will update with some photos.

p.s. I found some great 24V DC pumps that are DMX capable. I think I will have to install a AC/DC converter any how but having a 110V outlet makes everything more versatile.

 

[poconojoe]

You should have use #12 THHN individual conductors instead of of a stiff hard as nails UF cable in that 1/2" conduit. I'm surprised you even got it through there. UF cable has a tough outer casing used for direct burial without a conduit. It's OK, as long as you didn't damage it forcing it in there.
And why are you still considering using 24 Volt DC pumps?

 

[johnkim]

You should have use #12 THHN individual conductors instead of of a stiff hard as nails UF cable in that 1/2" conduit. I'm surprised you even got it through there. UF cable has a tough outer casing used for direct burial without a conduit. It's OK, as long as you didn't damage it forcing it in there.
And why are you still considering using 24 Volt DC pumps?

Hi Popconojoe,

I used UF cable use to add some additional protection against the element since it is weather and wet rated.

The reason for DC pump is I wanted to build a dynamic dancing fountain and using DMX protocol. DC pump can adjust flow rate easily compare to AC. I plan to use 3 1500GPH pump to power 3 jets. Each pump can be controlled individually and coordinated to create special effects along with some LED. This way, I can do away with any solenoid valves and complex plumbing.