Need ideas for the age old snake question

[Will Roth]

Hello everyone
Outdoor venue now with a permanent stage needs an answer for snakes and power. In the past trenches have been dug,they have been flown,cable ramps,bike rack. This is a dirt gravel mix sometimes with a sand topping and never fun to dig through

We are now hoping pipes will gget put in ( unless someone has a better answer).
We need to have access at 100' and 200' for bigger shows. they need to be sealed and opened as needed, and need to be sealed without anything getting in over the winter
Copper snakes,network,W4,feeder for spot lights, additional lighting, delay stacks and whatever insanity might get included as the next biggest cooler tour thinks up.
Obviously bigger is better and the more pipes ( thoughts on interference of 300 amps going through for lighting on top of the audio snake are welcome) how much space between?

Problems I have seen in the past:
1 Someone leaves the lid off and rain,water beer or worse gets in there and the first guy that season pulls his $10k snake through is pissed and has to re-loom it because it now looks like shit and the next day is a corporate show in a ballroom.
2 Drunken concert goers use it as a trash can or worse ;-) and it made it through fine at load in but at load out it seems to get stuck and before you are made aware of it, the 2 house guys have called over Big Earl and Bubba and they can pull a Chevy through that pipe if needed and you get there just as they fall backwards and you wait in horror as the end comes out without the W4
3 Guys who lay pipe run into big rock and decide they have 3-90 degree fittings in the truck and they will just go around it.
4 Oh you wanted us to pull the pull line back through when we pulled the snake out so you can use this pipe next week?
5. The opening band that got here at noon want to pull their lighting snake through even tough their set is at 5pm in direct sunlight and there are 100 movers at their disposal so they decide that pipe is plenty big and there is what seems to be a pull line so they just pull over top of the loom in there. Seems easy right?
6 The guy who has to pay for it realizes the one 12" PVC coupler is $96 and a T is $220 and the 45 degree is $150 and then you need 400' of pipe to have only 2 runs so he puts in 2- 6' pipes and tells you to make it work

Just make everything wireless right?

Thank you for your thoughts,comments and great ideas

Will

 

[Rob Timmerman]

Most of the highlighted issues relate to how the infrastructure is used maintained, and there's not much that can be done there to improve things from a design perspective. Intelligent placement of the access points can help matters, though. I'd also be tempted to enforce a limit of 180 degrees total bend between pull points (as required by TIA/EIA standards for data cabling, vs. the 360 degrees between pull points allowed by the NEC).

I'd also be tempted to review what currently gets run between stage and FoH, as it may be cost-effective to provide enough installed copper to reduce the amount the main pipes get used (I'm thinking a couple 1" pipes with some Cat6 dry lines and a couple of whatever your regional standard is for power between feeder and edison (think L21-30 or California). Maybe some fiber as well. The extra cost shouldn't be too bad, as the trenching cost is effectively fixed and the cost of the small-diameter conduit and Cat 6 is pretty low)

 

[Tim McCulloch]

We are working in a new municipal venue where they used 4" PVC. Multiple runs of it, but still only 4" with unknown (to us) bends. We found these when doing a site survey in preparing an estimate for base production services. The municipality *really* wants cables under ground and are looking at how to route an 8" run from SL to FOH. I'm sure it won't be cheap now that the landscaping is in.

They did have an answer about water/condensation - the public works dept has vacuum trucks used to clean out storm drains. Access points the the conduits are locking boxes so hopefully there won't be any "uh... yuck" moments from human miscreancy.

Provided there are minimal bends the 4" pipe will suffice for 1 FOH power run, 2 CAT5e and an 8 pair analog/AES drive snake. Barely.

 

[Randy Gartner]

I have been an electrical contractor of 30 years. I would suggest multiple runs of PVC. Anything from 2" up to 4". One reason many conduits have issues is because they don't use cleaner when installed and the joints leak or come apart. Use PVC cleaner on the outside of the pipe and inside of the joint before you glue. And don't use a multi purpose glue, use PVC glue. Glue both joints then push in, twist and hold for a few seconds. Because they are underground, they will still get moisture in from rain or condensation. You can use a wet/dry vacumn to pull as much water out as possible, but run a fish through with a rag tied to it to clean the rest out. And keep bends to a minimum,preferably one at each end. As far as access points, you can use what is called a "C" fitting in between long runs. It has a cover that is removeable.