RE: Oz ""experience tells me shorting of the wires with water won't be a problem ... Tap water is not too conductive""
Of course, if tiny hundreds of Ohms are okay, then may, however corrosion will going on with elephant steps. Generally, if any current over nanoAmps are expected, then to escape Faraday laws one must insulate wires in water. My city water grid have sth between 200 Ohm and 2000 Ohm depending from streetbloke, between two electrodes 1mm distance and 1x1 cm area each. Distilled water 10-100 kOhm, bisdistilled - few MOhms.

At 7 atmospheres any sealing must me mechanically stable; all the glue-droplets will be blown out at first 1/2 atm.

 

I think @cmartinez is working on an IoT cryptocurrency AI drone with blockchain kickstarter.

... that has an integrated mp3 player in it...

 

... that has an integrated mp3 player in it...

<OFFTOPIC>
And drives an animatronic penguin who shifts, flaps its wings and announces “Danger Will Robinson” when an alarm condition exists.
</OFFTOPIC>

Ok, back on topic, I promise.

 

... that has an integrated mp3 player in it...

And of course, laser cats!

 

@cmartinez If this is for potable water you may want to rethink making it from PVC pipe when being produced. Around here PVC type pipe isn't used for potable water, or at least not by people that know better. While copper has kind of gone out of style, the big thing now is Pex. And most of those fittings are brass. My middle son works for a guy that does remodeling and that is all they use now. http://www.pexinfo.com/

 

Ditto here. PVC is for drain water, not supply. I still use copper in my house but Pex is competitive.

 

@cmartinez If this is for potable water you may want to rethink making it from PVC pipe when being produced. Around here PVC type pipe isn't used for potable water, or at least not by people that know better. While copper has kind of gone out of style, the big thing now is Pex. And most of those fittings are brass. My middle son works for a guy that does remodeling and that is all they use now. http://www.pexinfo.com/

Yes, it's for potable water, and what you've mentioned is extremely valuable information. I'll give it careful consideration. Many thanks!

Question, why is PVC being shunned up there for this application? Because it's more fragile under pressure? Or is it a matter of hygiene?

 

Question, why is PVC being shunned up there for this application? Because it's more fragile under pressure? Or is it a matter of hygiene?

Mostly a matter of age. PVC was never that popular but it gets brittle with age and starts to leak and crack. It was used mainly in mobile homes, and they have now switched to PEX. Remodelers like it because it can be snaked within a wall with no joints and no tearing a wall out, just a small opening at a sill plate. Even most city water departments use it between the main and the meter now.

Another big reason is no soldering. Just like electronics your not allowed to use lead solder.

 

Mostly a matter of age. PVC was never that popular but it gets brittle with age and starts to leak and crack. It was used mainly in mobile homes, and they have now switched to PEX. Remodelers like it because it can be snaked within a wall with no joints and no tearing a wall out, just a small opening at a sill plate. Even most city water departments use it between the main and the meter now.

Another big reason is no soldering. Just like electronics your not allowed to use lead solder.

No one uses copper down here anymore, except for natural gas. The material has become too expensive, and it's common for thieves to vandalize houses while they're being built, and even attack the electrical wiring of public pedestrian lighting. Those SOB even stole my father's gravestone, which was made of bronze ... it's been replaced with granite, and all is well now.

 

I need to run a couple of 32 ga (0.009" diam) magnet wires through a 1-1/4" schedule 40 PVC pipe (wall thickness about 3.56mm, or a little more than 1/8"). Any ideas as to what is the best way to do it? Should I use a single hole for both wires and then seal it? What kind of sealing technique should I use? Or should I use a couple of screws/rivets acting as pass-through electrodes through the wall and use sealant on them? I would really like to make it work with the wires through a hole only, though.

The pipe is for domestic water use. Indoors conditions. Average pressure would be 35-40 psi, maximum 60 psi. Never as far up as 90 psi.

Hi,

A few too many posts for me to read so i'll just comment and see what you think.

Flowing water is a problem anywhere as it causes erosion.
Placing wires in a flow of water though a pipe is not the best idea.
What you should do is place a small tube of the same material as the pipe through the pipe, then put the wires through the tube. That way they are protected for a long time. So the large pipe would have a very narrow pipe stuck through it from side to side with the wires inside.

In any case you should have some kind of detection circuit to detect if the wires ever make contact with the water or if the large pipe starts to leak.

 

Hi,

A few too many posts for me to read so i'll just comment and see what you think.

Flowing water is a problem anywhere as it causes erosion.
Placing wires in a flow of water though a pipe is not the best idea.
What you should do is place a small tube of the same material as the pipe through the pipe, then put the wires through the tube. That way they are protected for a long time. So the large pipe would have a very narrow pipe stuck through it from side to side with the wires inside.

In any case you should have some kind of detection circuit to detect if the wires ever make contact with the water or if the large pipe starts to leak.

Thanks for your input, MrAl. The wires won't be directly exposed to the water flow, and this is for testing purposes only. Eventually, they will be embedded into the PVC material itself and won't even get wet. Right now I'm trying to find out the best way to seal the tube's wall as the wires run through it. But I think I've already found an acceptable solution.

 

No one uses copper down here anymore, except for natural gas.

What seems odd. Copper isn't allowed for gas here, other than the short flex line from the iron supply pipe to the appliance. And those are brass corrugated tubes not copper. And gas lines underground are now a PEX like pipe from the main.

 

Thanks for your input, MrAl. The wires won't be directly exposed to the water flow, and this is for testing purposes only. Eventually, they will be embedded into the PVC material itself and won't even get wet. Right now I'm trying to find out the best way to seal the tube's wall as the wires run through it. But I think I've already found an acceptable solution.

Hola César

Not a reply to anything in this thread, but today, for the first time, I clicked on your David Mikkelson link.

Seriously, ¡wow!

 

Hola César

Not a reply to anything in this thread, but today, for the first time, I clicked on your David Mikkelson link.

Seriously, ¡wow!

Yeah ... that anecdote has been a continuous inspiration for me ... what a difference it makes when one is thoroughly motivated and there's no one there to tell you that it can't be done!

 

Hola César

Not a reply to anything in this thread, but today, for the first time, I clicked on your David Mikkelson link.

Seriously, ¡wow!

Was that the same kid who didnt realize regular humans could not walk on water and thus walked on water?

 

Was that the same kid who didnt realize regular humans could not walk on water and thus walked on water?

Who?

 

PVC is for drain water, not supply.

Down here on the Coast almost all houses are built "Slab on Grade" which means the plumbing is under the concrete slab. Seems copper is more prone to bursting/leaking than PVC is. Much cheaper than copper also and "Lead-Free" so is the preferred plumbing product used now. Slab on Grade construction has a concrete foundation footer and concrete block courses up to the floor level. The top course is a L shaped block for the floor slab concrete to flow into when poured. Before pouring the slab the fill dirt (it is filled with tamped dirt to the floor bottom level) is termite treated and all plumbing stubbed out. The one house I heard of with overhead piping from the attic suffered extreme failure from freezing. It can get down to ~20°F in the winter here (rarely).
"