pump wires inside the supply piping?

[Raucina]

I have to pioneer some 1" black poly pipe through a canyon and hillside that even a dozer will not approach - in this mountain climate, freezing is short and light, the pipe will be on the surface and soon covered by leaves and debri. Chatting with my well driller, he said he has seen the wires run from the point of use to the well head INSIDE the water supply piping. One run of pipe - no conduit. Seems like an elegant solution but an extraordinary one. He did not know of the fitting used to put the wires into the pipe and out again at the well head - is such a thing made? Ideas to make one? No inspectors here, and of course the wires are going to hang in the drinking water anyway within the well - why not? Any ideas for the wires in and out without creating an electric fountain? PSI maybe 120 and 3 10g wires . I would not dare ask anyone to calculate the flow restriction from the wires- but it is of some import, especially at the exit points. Pumping to a large tank, so gpm can be small.

 

[Bob NH]

Anti-freezing tape is installed in pipe without problems. Wire to submersibles is wet all the time.

I would use wet-rated. Much of the single strand wire available is THHN/THWN/MTW. Temperature will certainly not be an issue in the pipe. You want one piece if possible. You might run the last 20 ft through copper and the ground it at the delivery end by attaching it to the equipment ground at the electrical source point.

To reduce pressure drop, I would use the smallest flow and not use twisted wires.

The electrical fitting will be non-standard. There may be something available. My first thought would be to run each wire through a 1/4 fitting with some kind of non-metallic packing. Most of the plastic fittings that I have seen are rated at 100 psi, but you might find some that would handle 120 psi.

 

[Sponsor]

 

[Speedbump]

It seems to me a standard nylon nut and ferrell would work for the water proof fittings at either end. You would have to use a round rubber or plastic jacketed wire for the ferrell to make a good seal. You would have to also find a wire size that would be very close to the tubing size the ferrell was designed to seal.

bob...

 

[Valveman]

Valveman

Grundfos makes an electrical fitting like that they use in their canned submersible pump systems. Not cheap but might give you some ideas.

 

[Raucina]

Thanks for the help... I am going to try the 1/4" fitting outlet - one per wire- with a nylon compression fitting. Prior to hooking the assembly up, I am thinking to fill the outlet point from the inside with epoxy or silicone to back up the sealing area.

 

[Mikey]

Are both ends above ground? I was thinking you could terminate each end at a tee, and bring the wires out through a cap in the arm of the tee. That would give you a solid surface to install your through-fittings. You could look into an aircraft bulkhead through-fitting (aka "Cannon plug") which is liquid- and air-tight, or any similar plug-and-socket arrangement. The wires are crimped or soldered on one side, and a plug goes into the other.

 

[Speedbump]

How do they waterproof the wires where they meet the plug Mikey?

I would like to see a device like this, I can see where it could come in real handy for some folks.

Of coarse we don't have to worry about freezing here, do we Mikey?

bob...

 

[Gary Slusser]

Endot made PE pipe with the cable on the outside under a molded PE cover that was part of the pipe. They stopped making it just a year or two ago but I'll bet some supply house might have some or be able to find some laying around in a warehouse somewhere. Or contact Endot http://www.endot.com/products/.

 

[Raucina]

Cheers to Endot for thinking outside the box - great idea that probably wont get to the mainstream because of all the Luddites lurking in the corners... If memory serves me, they were the Englishmen that smashed the first steam engines that threatened all workmans lives in the toddler days of the industrial [r]evolution. What would they think today at a mainstream auto factory?

 

[Cass]

Not sure about this but is there any concern about chemicals leaching from the wire insulation into the water?

 

[Mikey]

Bulkhead fittings

There are several ways to get a cable through a surface in a watertight or airtight manner. The one I was thinking of is a plug-and-socket arrangement usually called a "Cannon Plug", although there are several manufacturers and variations on a theme. The socket is usually mounted on the surface, either with screws and nuts or as a threaded bushing kind of thing. There are a number of contacts hermetically sealed in the socket, solderable or crimped on one end, and recpetacles on the other. The plug plugs into the socket, usually on the "outside" of whatever you're sealing up, and is fastened via a threaded ring, kind of like a slipnut. On the inside, the wires are soldered or crimped onto the connectors, and a gooey sealant is slopped all over to protect the connections from corrosion, etc.

Before I get up to 1000 words in a futile attempt to describe these things, here's a picture of some:

http://www.alvatek.com/cms/amphenol-97-series-crimp-type-cylindrical-connectors.php

Incidentally, Snap-On makes a special set of pliers with padded jaws to use on the cannon-plug rings that works great on threaded chrome fixtures without scratching them:

http://buy1.snapon.com/catalog/item.asp?P65=&tool=all&item_ID=7220&group_ID=798&store=snapon-store&dir=catalog

 

[Speedbump]

I should have thought of Amphenol fittings. How many PL259's have I installed on the end of coax? That would work great. It is the gookie puckie I would be leary of. Does anyone make something that can just be put on like Silicone that would be safe inside a water pipe with 230 volts?

bob...

 

[Gary Slusser]

Cheers to Endot for thinking outside the box - great idea that probably wont get to the mainstream because of all the Luddites lurking in the corners... If memory serves me, they were the Englishmen that smashed the first steam engines that threatened all workmans lives in the toddler days of the industrial [r]evolution. What would they think today at a mainstream auto factory?

I seriously looked into using it but, it makes a roll of pipe much heavier with only one guage of cable in each roll, and running around with say a 500' roll of it, in the rare event I'd need new cable, wasn't appealing. I already had 3-5 rolls of cable of various guage on the truck, so I never bought any of it. I don't think many others did either and a far as I know, they stopped making it. I would think it would be nice for new construction since you'd know what guage cable you need, if you could handle the heavier rolls. Actually the wasted cable along with left over pipe was probably its downfall.

 

[Raucina]

Yes, the waste would be unmanageble - it would have to be a made to order sort of item, call in a length and wire gauge and a lead length and get it in a few days - that would be a whole new business for someone.