Ideas for outdoor con box or other ideas

Status
Not open for further replies.
F

fastline

Senior Member
Location
midwest usa
Occupation
Engineer
I am having to work a design that is turning into a cluster F... Basically 150ft from a building, I need to serve up 120V to a powered gate, a 2 conductor low energy switching circuit to activate gate, 2 CAT6 cables for each card reader at gate, then at least 2 CAT6s for 2 cameras out there. What I am trying to do is clean up how all this enters the building, rather than a line of LBs... Looks like crap, but.....

I am also torn on that 2 conductor going to gate opener. Really would like to ride it in the pipe with the power, but I know it should not be in there.

More to the point, due to distance and complexity, I was thinking of setting a con box or similar at about the 100ft mark because I have to come out of the ground there anyway. My thought was to do pull loops in there so if something gets damaged out there, there is an easier way to repair rather than a complete home run. I was looking at communications type pedestals. Never have really used them though. Not even sure this is the right strategy.
 
fastline said:
I am also torn on that 2 conductor going to gate opener. Really would like to ride it in the pipe with the power, but I know it should not be in there.
Click to expand...
I'm not sure why not, at least not from an NEC perspective. As long as the two have an insulation rating at least as high as the power voltage (a very high probability), you can put them in the same conduit as the power conductors.

Now, as to whether the "low voltage" game rules prohibit the sharing, I have no facts to offer. Perhaps someone with experience in that area (I have none) can chime in.
 
charlie b said:
I'm not sure why not, at least not from an NEC perspective. As long as the two have an insulation rating at least as high as the power voltage (a very high probability), you can put them in the same conduit as the power conductors.

Now, as to whether the "low voltage" game rules prohibit the sharing, I have no facts to offer. Perhaps someone with experience in that area (I have none) can chime in.
Click to expand...
I think it is largely my general practice to keep control, low voltage, communications separate, but I may have to concede on this one. I always think 'what if'... and if somehow power made it on that 2 wire switching cable, it would blow up the access control unit. Basically that 2 wire just gets closed when commanded from the access control and that signal is relayed to the gate opener to open.
 
fastline said:
. . . and if somehow power made it on that 2 wire switching cable. . . .
Click to expand...
That is why all conductors sharing a conduit must have an insulation system rated at least as high as the highest voltage conductor in the set. That makes this an unnecessary what if.
 
My worry on having them all inside the same conduit would be induced voltages caused by the long parallel run. Waaaay back before I took up residence in the low voltage (Modbus/BACnet/SNMP) world, I worked at a motor shop that did VFD installation and repair. We got called out to a factory where a 400HP VFD was physically isolated, with the breaker literally racked out, yet it would keep powering up with the display screen coming online and acting as if it were ready to rock. Of course, as soon as you tried to make the motor move, the thing would fall on its face, but it wasn't until one of the maintenance guys pulled out their prints and we saw it sharing a couple hundred feet of tray with two other drives that the light bulbs went 'ping!'
 
charlie b said:
I'm not sure why not, at least not from an NEC perspective. As long as the two have an insulation rating at least as high as the power voltage (a very high probability), you can put them in the same conduit as the power conductors.

Now, as to whether the "low voltage" game rules prohibit the sharing, I have no facts to offer. Perhaps someone with experience in that area (I have none) can chime in.
Click to expand...
i bet the gate control is class 2 and cant be in the power conduit
 
this doesnt seem like that big of a deal. 2 LB out of the building one LV and one power, handhole out at the gate location with pipes to each point of use. or if you want to pipe it all separately you could set a single pullbox on the building for all the LV and nipple through the wall.
 
I was informed that a security light will need installed on the circuit mentioned above, which will will change this a bit and require a field splice of the 120V circuit inside the secondary pedestal. I'm am now left scratching my head on an appropriate and approved splice inside that box? I planned to bring all conduits up in sweep 90s inside the pedestal. Sort of feel splice tape is less ideal. Ideas on a better method?
 
Todd0x1 said:
why a pedestal instead of a handhole?
Click to expand...
Well, I guess we can discuss it but my thought process is since we are pulling CAT6, non-gel wire, I want to keep moisture out as long as possible, so the thought was to bring the conduit sweeps up well above grade. The reason for the junction in the first place is only for an "oh-shit", so a splice can be made at that box if ever needed, and we now know we need a 120V splice there anyway.

I just find keeping connections above grade tends to prolong them, but I am finding insane problems finding any pedestals locally.
 
fastline said:
Well, I guess we can discuss it but my thought process is since we are pulling CAT6, non-gel wire, I want to keep moisture out as long as possible, so the thought was to bring the conduit sweeps up well above grade. The reason for the junction in the first place is only for an "oh-shit", so a splice can be made at that box if ever needed, and we now know we need a 120V splice there anyway.

I just find keeping connections above grade tends to prolong them, but I am finding insane problems finding any pedestals locally.
Click to expand...

You should not have any intermediate splices in the CAT6
 
Todd0x1 said:
You should not have any intermediate splices in the CAT6
Click to expand...
I don't plan to, but if bad things happen, I am designing the ability to patch it in the JB. Main reason is com is primarily serial RS232. Low freq, it should work.

Otherwise, I only want spare cable pulled into the JB, looped, and sent back out.

I highly suspect fiber will own all of this space in short order anyway.
 
fastline said:
I don't plan to, but if bad things happen, I am designing the ability to patch it in the JB. Main reason is com is primarily serial RS232. Low freq, it should work.

Otherwise, I only want spare cable pulled into the JB, looped, and sent back out.

I highly suspect fiber will own all of this space in short order anyway.
Click to expand...
rs232 for 150+ft? youre probably going to want to use rs485 converters
 
wiegand. Technically will prob get replaced soon enough, but the pipes are there is wires change. I don't expect the need to splice in the JB, but it's there. At the very least, This pull could not be completed without the JB. Too many bends to deal with.
 
Todd0x1 said:
dont you want to use wiegand cable for the readers and not cat6?
Click to expand...
Only thing I can say is the control system info is super vague other than to use twisted pair wire, and it is currently running on 5e cable.

This whole thing is a 'kick the can' deal for them until a decision is made to replace the entire access system. Thus why everything is being designed around total replacement of cables .
 
fastline said:
Only thing I can say is the control system info is super vague other than to use twisted pair wire, and it is currently running on 5e cable.

This whole thing is a 'kick the can' deal for them until a decision is made to replace the entire access system. Thus why everything is being designed around total replacement of cables .
Click to expand...
good deal. build to spec and let the technical details be someone elses problem.
 
Todd0x1 said:
good deal. build to spec and let the technical details be someone elses problem.
Click to expand...
To an extent. I know the people, which is why I was brought in. I'm trying to give them a real world solution but of course always a beer budget.

The access system has run 10+ yrs on 5e wire. Common sense says it will work on 6. From a serial communication side, I could defend CAT6 all day, so it would come down to the power side. I just don't know but likely less than 1W. Actually somewhere I have numbers for the readers but it's small. .

I'm more frustrated they put a 120V gate opener in, 300ft from a service, in an industrial area. Like, why?
 
Status
Not open for further replies.
Top