Question on wiring.

[Securitymaster 0]

I have seen some debates over time about the proper piping that needs to be used in order to do a residential building install of CCTV.

 

Some say use EMT, while others say to use PVC. I'm in CT, so what is the standard? Local building inspector said that he really doesn't know since local code doesn't mention CCTV.

 

Thanks.

[CraigVM62 0]

guessing your refering to pipe for use in trenches or exterior of building ? There are really no electrical codes that governs over low voltage other than that installed within the structure / walls or distance to ground in overhead drops. In that regards it would fall mostly under the common sense code for you the installer. I have only used EMT for CCTV in the few interior commercial installations I have performed. In both Commercial and Residential I have always used PVC to protect exposed exterior cabling or trench work. Main advantage I can see with EMT is that if your good with an EMT bender, you save yourself the cost of buying 45 and 90 degree fittings and can do offsets going into boxes etc.

[Securitymaster 0]

The install is going to be exterior attached to the building. My main concern was that some states don't like EMT in the exterior because of lighting issues, plus the metal is conductive if a wire (we are talking 120 VAC here) get's stripped, then it could shock whoever touches it.

[CraigVM62 0]

The install is going to be exterior attached to the building. My main concern was that some states don't like EMT in the exterior because of lighting issues, plus the metal is conductive if a wire (we are talking 120 VAC here) get's stripped, then it could shock whoever touches it.

 

The point about installing what might become a lighting rod is a good one. Despite all the rain we get here in the Pacific NW. Lightning is surprisingly uncommon.

When EMT is used for electrical "high voltage" in commercial applications, it becomes the grounding for the electrical system. The only time a ground conductor "green" is pulled is if there will be a break in the EMT that is not conductive eliminating the EMT as your ground back to the electrical panel. That ground conductor then re-grounds the EMT past that break. So if a hot conductor should touch the EMT, it should instantly trip the breaker for that circuit. Forgive me it all that is old news to you.

I would also consider the issue of rust if EMT is used in exterior applications. Even galvanized EMT will rust at cut points, fittings and where scuffed. Other than the cost of running plastic conduit, I can't see any advantages of EMT over it for low voltage applications.

[CSG 0]

I wouldn't run EMT in exterior applications since it's not water proof, and water may collect inside. Use either PVC or pipe (threaded fititngs).

[Securitymaster 0]

I wouldn't run EMT in exterior applications since it's not water proof, and water may collect inside. Use either PVC or pipe (threaded fititngs).

 

I think that Threaded will be the way to go, because another concern is that the location of the install is a good bulding, but other people in the area are the problem, so I don't want them to mess with the camera or the line. I've seen some installations that the PVC lines are plain cut thru.

[rory 0]

I wouldn't run EMT in exterior applications since it's not water proof, and water may collect inside. Use either PVC or pipe (threaded fititngs).

 

I think that Threaded will be the way to go, because another concern is that the location of the install is a good bulding, but other people in the area are the problem, so I don't want them to mess with the camera or the line. I've seen some installations that the PVC lines are plain cut thru.

 

yeah but then they can just disable the cameras easily anyway ..

[jeromephone 6]

I was in the local electrical supply store and they had a device that looks like a spring that you insert into pvc pipe and then you can use a regular conduit bender on pvc pipe. I have not tried it yet but it would save on fittings and give you the abililty to make those complicated bends. (Once the bend is made the spring thing is pulled out)

[Securitymaster 0]

uh!!, very interesting, I will research that. Thanks.

[CraigVM62 0]

I was in the local electrical supply store and they had a device that looks like a spring that you insert into pvc pipe and then you can use a regular conduit bender on pvc pipe. I have not tried it yet but it would save on fittings and give you the abililty to make those complicated bends. (Once the bend is made the spring thing is pulled out)

 

I have never heard of that before ..... I am guessing you plug it in so to heat up the PCP Pipe, but from the inside ??? Or, do you insert it into the pipe and then heat up the pipe with the conventional means, with the spring helping the pipe to keep it's shape when bent so it doesn't buckle ???

 

Sounds Interesting

[Securitymaster 0]

 

yeah but then they can just disable the cameras easily anyway ..

 

Well, if you put them high enough that they can't reach without a ladder, it might just give the cameras a chance.

[rory 0]

 

yeah but then they can just disable the cameras easily anyway ..

 

Well, if you put them high enough that they can't reach without a ladder, it might just give the cameras a chance.

 

 

paint gun buddy

 

also, higher than a normal ladder is too high for a camera, should be able to reach the camera easily for maintenance plus the higher you go the more you lessen the FOV ..

[JSCCTV 0]

I use a product called flex tube. I usualy buy it from a home depot. it comes in a 100' roll. It is dark gray and there is no need for elbows,45-90. Cut the length you need, pull cable through and then bend any which way you need it. Just use clamps to hold it. I use this all the time inside & Outside. It looks real neat and professional.

[replanet 0]

Most homes have at the very least a crawl space under the roof. There should be an air gap between the roof and the walls for venting covered with some mesh wire. If the customer has a nice home and is also willing to spend a little more on the harder install I would wire all through the crawl space, and install the cameras under the eve if its low or just make a straight vertical drop to each individual camera. I think most residential customers would prefer that to a perimeter pipe.

[Securitymaster 0]

Most homes have at the very least a crawl space under the roof. There should be an air gap between the roof and the walls for venting covered with some mesh wire. If the customer has a nice home and is also willing to spend a little more on the harder install I would wire all through the crawl space, and install the cameras under the eve if its low or just make a straight vertical drop to each individual camera. I think most residential customers would prefer that to a perimeter pipe.

 

 

Only problem is that this is a 50 year old residential building with 140 units. We figured out how to do some things, but I will look into everything that you guys have suggested.

[rory 0]

knock it down and build it new ..

[jeromephone 6]

I don't think you have to heat the pipe at all I will stop there tomorrow and find out the product name etc.

[Securitymaster 0]

Thanks!!

[mariner 0]

If this is a comercial building it would be run in EMT. If outside we would use compression fitting. PVC would not be used unless underground, then it would be grey PVC which is for electrical; no other color is permitted. Being low voltage it is not reguired to be in conduit, unless there is a city addemdum to the code which usually is only on fire alarm. Rigid conduit (threaded) would only apply underground. Emt is considered a mechanical ground not an electrical ground (ground wire) and wouldnt pose much of a threat to lightning strikes.

[ben_indo 0]

so far I see 2 sizes of such spring 3/4" and 1" in the market, it works great, but not every type of pvc pipe are design to be bend, hi impact electrical type pvc pipe usually are bendable, and no heat required.

 

we have been using it for years and happy with it.