Did a small job yesterday making a short run of outdoor conduit
watertight; homeowner gave me the connectors (elbows and compression
fittings) and had me replace the existing ones.

The compression connectors were labeled "concrete tight", and when I
asked him if that meant they were truly watertight, he said he was told
they were by someone where he bought them (which I think was a big
orange store).

So what's the recommended practice to make metal conduit watertight?
Yes, I know one can use plastic, but I'm interested in how to make the
steel stuff withstand weather.

I have seen wiring failures in outdoor conduit caused by the ingress of
water; in one case, a nick in a wire caused by pulling it caused
corrosion to the point that the wire actually broke in two.

(This installation is mostly under an eave, so watertightness isn't
super-critical, but keeping water out is a Good Thing.)


--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet

"David Nebenzahl" wrote in message
.com...
Did a small job yesterday making a short run of outdoor conduit
watertight; homeowner gave me the connectors (elbows and compression
fittings) and had me replace the existing ones.

The compression connectors were labeled "concrete tight", and when I asked
him if that meant they were truly watertight, he said he was told they
were by someone where he bought them (which I think was a big orange
store).

So what's the recommended practice to make metal conduit watertight? Yes,
I know one can use plastic, but I'm interested in how to make the steel
stuff withstand weather.

I have seen wiring failures in outdoor conduit caused by the ingress of
water; in one case, a nick in a wire caused by pulling it caused corrosion
to the point that the wire actually broke in two.

(This installation is mostly under an eave, so watertightness isn't
super-critical, but keeping water out is a Good Thing.)


--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet

If you're using EMT, use rain-tite fittings. If your wires are THWN, it
doesn't matter if they get wet

On 11/14/2009 12:07 PM RBM spake thus:

"David Nebenzahl" wrote in message
.com...

Did a small job yesterday making a short run of outdoor conduit
watertight; homeowner gave me the connectors (elbows and compression
fittings) and had me replace the existing ones.

The compression connectors were labeled "concrete tight", and when I asked
him if that meant they were truly watertight, he said he was told they
were by someone where he bought them (which I think was a big orange
store).

So what's the recommended practice to make metal conduit watertight? Yes,
I know one can use plastic, but I'm interested in how to make the steel
stuff withstand weather.

I have seen wiring failures in outdoor conduit caused by the ingress of
water; in one case, a nick in a wire caused by pulling it caused corrosion
to the point that the wire actually broke in two.

(This installation is mostly under an eave, so watertightness isn't
super-critical, but keeping water out is a Good Thing.)

If you're using EMT, use rain-tite fittings. If your wires are THWN, it
doesn't matter if they get wet

.... as long as there are no breaks in the insulation.

So what's the diff betwixt raintight and "concrete tight"?


--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet

"David Nebenzahl" wrote in message
.com...
On 11/14/2009 12:07 PM RBM spake thus:

"David Nebenzahl" wrote in message
.com...

Did a small job yesterday making a short run of outdoor conduit
watertight; homeowner gave me the connectors (elbows and compression
fittings) and had me replace the existing ones.

The compression connectors were labeled "concrete tight", and when I
asked him if that meant they were truly watertight, he said he was told
they were by someone where he bought them (which I think was a big
orange store).

So what's the recommended practice to make metal conduit watertight?
Yes, I know one can use plastic, but I'm interested in how to make the
steel stuff withstand weather.

I have seen wiring failures in outdoor conduit caused by the ingress of
water; in one case, a nick in a wire caused by pulling it caused
corrosion to the point that the wire actually broke in two.

(This installation is mostly under an eave, so watertightness isn't
super-critical, but keeping water out is a Good Thing.)

If you're using EMT, use rain-tite fittings. If your wires are THWN, it
doesn't matter if they get wet

... as long as there are no breaks in the insulation.

So what's the diff betwixt raintight and "concrete tight"?


--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet


One is designed to keep out rain, the other concrete. Some concrete tight
fittings are also rain tight, but not all.

Did a small job yesterday making a short run of outdoor conduit
watertight; homeowner gave me the connectors (elbows and compression
fittings) and had me replace the existing ones.

The compression connectors were labeled "concrete tight", and when I asked
him if that meant they were truly watertight, he said he was told they
were by someone where he bought them (which I think was a big orange
store).

So what's the recommended practice to make metal conduit watertight? Yes,
I know one can use plastic, but I'm interested in how to make the steel
stuff withstand weather.

I have seen wiring failures in outdoor conduit caused by the ingress of
water; in one case, a nick in a wire caused by pulling it caused corrosion
to the point that the wire actually broke in two.

(This installation is mostly under an eave, so watertightness isn't
super-critical, but keeping water out is a Good Thing.)



*Under the eave is considered a damp location, not a wet location. I don't
recall seeing watertight connectors for EMT. The compression connectors are
considered rain tight. Use conductors rated for wet locations and be
careful not to nick them and they should be fine. Use weatherproof boxes
with weatherproof covers.

When I did conduit jobs in concrete decks and such I always wrapped the
connectors with duct or gaffers tape. Even if they were considered concrete
tight, without the tape wrap some concrete juice would always seep in and
harden in the conduit.

PVC and liquid tight conduits are waterproof with proper fittings.

On Nov 14, 1:59*pm, David Nebenzahl wrote:
On 11/14/2009 12:07 PM RBM spake thus:





"David Nebenzahl" wrote in message
s.com...

Did a small job yesterday making a short run of outdoor conduit
watertight; homeowner gave me the connectors (elbows and compression
fittings) and had me replace the existing ones.

The compression connectors were labeled "concrete tight", and when I asked
him if that meant they were truly watertight, he said he was told they
were by someone where he bought them (which I think was a big orange
store).

So what's the recommended practice to make metal conduit watertight? Yes,
I know one can use plastic, but I'm interested in how to make the steel
stuff withstand weather.

I have seen wiring failures in outdoor conduit caused by the ingress of
water; in one case, a nick in a wire caused by pulling it caused corrosion
to the point that the wire actually broke in two.

(This installation is mostly under an eave, so watertightness isn't
super-critical, but keeping water out is a Good Thing.)

If you're using EMT, use rain-tite fittings. If your wires are THWN, it
doesn't matter if they get wet

... as long as there are no breaks in the insulation.

So what's the diff betwixt raintight and "concrete tight"?

--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet

Concrete tight connectors are designed for use where emt, connectors &
boxes are to embedded in concrete. Concrete, while semi-fluid when
placed, is a far cry from water. Most concrete mixes (ideally) have
very little excess water, so unless excessively wet or excessively
vibrated, will not "bleed" a lot. Concrete forms only needed to be
failrly tight, not water tight.

Concrete just cannot leak into small but visible cracks the way water
can.

Rain is......well..... water but a rain condition is not the same as
full continuously submerged condtion...... so rain tight is not water
tight.

There are electrical enclosures (& this is getting out of my area of
experience) that are for indoor use, ones for outdoor that are rated
rain tight, ones for washdown, ones for industrial environment, ones
that are fully submersible.

Fittings & enclosures give increasing levels of service.

Kinda like clothing for a person; dry weather clothes, rain gear
(rain coat or umbrella) , wet suit, dry suit, NBC suit.

So if fittings are rated concrete tight, they're definitely fin for
indoor or under an eave but I wouldnt use them exposed to the
elements....I switch to the compression style that I believe are rain
tight.

cheers
Bob

On 11/14/2009 4:06 PM DD_BobK spake thus:

So if fittings are rated concrete tight, they're definitely fin for
indoor or under an eave but I wouldnt use them exposed to the
elements....I switch to the compression style that I believe are rain
tight.

The concrete-tight connectors *are* compression fittings. They look
pretty watertight, but who knows? (Certainly better than the
screw-tightened connectors that were there before.)


--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet

David Nebenzahl wrote:
Did a small job yesterday making a short run of outdoor conduit
watertight; homeowner gave me the connectors (elbows and compression
fittings) and had me replace the existing ones.

The compression connectors were labeled "concrete tight", and when I
asked him if that meant they were truly watertight, he said he was told
they were by someone where he bought them (which I think was a big
orange store).

So what's the recommended practice to make metal conduit watertight?
Yes, I know one can use plastic, but I'm interested in how to make the
steel stuff withstand weather.

I have seen wiring failures in outdoor conduit caused by the ingress of
water; in one case, a nick in a wire caused by pulling it caused
corrosion to the point that the wire actually broke in two.

(This installation is mostly under an eave, so watertightness isn't
super-critical, but keeping water out is a Good Thing.)


Ok, I have no expertise in any of this, BUT. I figure that water can get
into any place that is below grade, and a lot of places that are above
grade. Trying to make something impervious to water is pretty much
not possible. So I would go ahead and use quality conduit, and then
use conductors that can be immersed in water, figuring that at some
time they will be.

Bill

On 2009-11-15, DD_BobK wrote:

So if fittings are rated concrete tight, they're definitely fin for
indoor or under an eave but I wouldnt use them exposed to the
elements....I switch to the compression style that I believe are
rain tight.

Compression fittings come in various flavors, e.g. concrete tight or
rain-tight. I think they may all be concrete tight, but they
definitely are not all rain tight.

Cheers, Wayne

On 2009-11-14, David Nebenzahl wrote:

I have seen wiring failures in outdoor conduit caused by the ingress
of water; in one case, a nick in a wire caused by pulling it caused
corrosion to the point that the wire actually broke in two.

I think this is the wrong emphasis. The wiring failure was caused by
the nick in the wire; water in exterior conduit is a given, from rain
or just from condensation.

Cheers, Wayne

On 11/15/2009 9:35 AM Wayne Whitney spake thus:

On 2009-11-15, DD_BobK wrote:

So if fittings are rated concrete tight, they're definitely fin for
indoor or under an eave but I wouldnt use them exposed to the
elements....I switch to the compression style that I believe are
rain tight.

Compression fittings come in various flavors, e.g. concrete tight or
rain-tight. I think they may all be concrete tight, but they
definitely are not all rain tight.

So are you saying the ones I coulda/shoulda used would say "RAIN TIGHT"
on the package? These ones said "CONCRETE TIGHT".


--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet

On 11/15/2009 9:39 AM Wayne Whitney spake thus:

On 2009-11-14, David Nebenzahl wrote:

I have seen wiring failures in outdoor conduit caused by the ingress
of water; in one case, a nick in a wire caused by pulling it caused
corrosion to the point that the wire actually broke in two.

I think this is the wrong emphasis. The wiring failure was caused by
the nick in the wire; water in exterior conduit is a given, from rain
or just from condensation.

Yes. I guess the take-away here is to be extra careful fishing and
bending wires in outdoor conduit so as not to nick them.

The little job I had to do revealed one stranded and one solid wire in
the existing conduit. It really is a bitch to re-pull solid wire without
nicking it.


--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet

On Nov 14, 5:54*pm, David Nebenzahl wrote:
On 11/14/2009 4:06 PM DD_BobK spake thus:

So if fittings are rated concrete tight, they're definitely fin for
indoor or under an eave but I wouldnt use them exposed to the
elements....I switch to the compression style that I believe are rain
tight.

The concrete-tight connectors *are* compression fittings. They look
pretty watertight, but who knows? (Certainly better than the
screw-tightened connectors that were there before.)

--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet

The concrete light ones that I have used were not compression
style.....slip on w/ a set....concrete tight per the carton labeling.

I was actually pretty surprised that the slip on type were rated
"concrete tight" but my subsequent experience with concrete showed
that for something to perform "concrete tight" isn't all that hard.

cheers
Bob

On Nov 15, 1:19*pm, David Nebenzahl wrote:
On 11/15/2009 9:39 AM Wayne Whitney spake thus:

On 2009-11-14, David Nebenzahl wrote:

I have seen wiring failures in outdoor conduit caused by the ingress
of water; in one case, a nick in a wire caused by pulling it caused
corrosion to the point that the wire actually broke in two.

I think this is the wrong emphasis. *The wiring failure was caused by
the nick in the wire; water in exterior conduit is a given, from rain
or just from condensation.

Yes. I guess the take-away here is to be extra careful fishing and
bending wires in outdoor conduit so as not to nick them.

The little job I had to do revealed one stranded and one solid wire in
the existing conduit. It really is a bitch to re-pull solid wire without
nicking it.

--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet

Use wire lube, it really helps.


cheers
Bob

On 11/15/2009 10:04 PM DD_BobK spake thus:

On Nov 15, 1:19 pm, David Nebenzahl wrote:

On 11/15/2009 9:39 AM Wayne Whitney spake thus:

On 2009-11-14, David Nebenzahl wrote:

I have seen wiring failures in outdoor conduit caused by the ingress
of water; in one case, a nick in a wire caused by pulling it caused
corrosion to the point that the wire actually broke in two.

I think this is the wrong emphasis. The wiring failure was caused by
the nick in the wire; water in exterior conduit is a given, from rain
or just from condensation.

Yes. I guess the take-away here is to be extra careful fishing and
bending wires in outdoor conduit so as not to nick them.

The little job I had to do revealed one stranded and one solid wire in
the existing conduit. It really is a bitch to re-pull solid wire without
nicking it.

Use wire lube, it really helps.

Thanks. Next time I will.


--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet