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dthompson

Best Practice for Running Cable from building to pole

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I am wondering what the best practice (and any advice for) running Siamese wire from a building to pole would be. The run is between 80-100'. What is the max distance I can run wire? Do I need to run a supporting cable first?

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I am wondering what the best practice (and any advice for) running Siamese wire from a building to pole would be. The run is between 80-100'. What is the max distance I can run wire? Do I need to run a supporting cable first?

Use a "stringer" cable and hang your Siamese from it. I've used stainless steel winch cable for that function and had excellent results. Space your stays at around 24" apart.

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Before you start "stringin" wire/cable do a read on messengered drop cables, whatever cable you run...cctv, tv etc, there are several guidlines and safety factors. You must also take into consideration environmental conditions as well..in colder climates rain turns to ice and ice turns to added load etc. also is the pole mechanicaly sound, is it privately owned, proper rigging.. a failure can cause serious injury as well property damage if a cable fails and gets picked up by wind, here is a good read for you on the basics: http://www.timesfiber.com/pdfs/Technical%20Notes/1039a-tn.pdf

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The "Post" (and I should have been more specific, sorry) is a privatley owned,

light post. Its like a wooden electric pole, foot or so diam. The light is up high and I was looking into placing the camera a ways below it. I will check the link on rigging. We do have cold weather, that is a factor, and one of my concerns. Its a paved lot, so trenching is not really a good option, but is still one. Thanks for the thoughts.

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I dont know what the regulations are in your country, however running close to mains power here without good seperation distance is a NO-NO...If you are going to run the cable inside the pole, beware of the mains power.

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dtthompson stated that it was a wooden Pole, so his run would be surface mounted. His "wooden post" more than likely timber/log and hopefully pressure-treated....(older wooden utility type poles in the US were almost always treated with creosote, nasty stuff) ... other materials steel, concrete, and composites (fibreglass) are being used these days for utility.... Its not at all uncommon for telecommunication network/signal equipment to be situated on poles ...analogue repeaters and other outside plant equipment have been mounted against poles for years, and now digital equipment multiplexing/demultiplexing ,digital repeaters etc... electric POCOs often lease lines to cable television, telephone, street lighting,traffic signals etc... private services share poles, either in joint ownership or by renting space to each other. A private pole such as his still must adhere to safe electrical pratices however. I would assume and hope that the fixture already mounted is placed with a outdoor box and proper wire in conduit. There should always be a safe gap and isolation between power HV lines and LV signal wires, and he should pay close attention to correct aerial rigging standards.

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I understand some of the electrical issues that may arise out of all this. I am beginning to rethink the whole placing the camera on the pole idea, just thought it would be best placement. The ONLY electricity running to this pole is for the light. The wires coming to the light are run overhead from the opposite direction I was thinking of coming in from. I figured as long as I was far enough below the light, I was safe. I just was not sure of the distance that running cable alone would take. I understand now that in a cold weather area, with snow and ice, I will have to have a support cable.

I understand I am new to the post and will try to word my scenario much better next time.

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Reviving and old thread....better than starting a new one I guess LOL!

 

I have done a few aerials but I have been using standard Siamese cable used for indoors. Now the PVC jacket should last for probably longer than the hardware before breaking down. But....

 

Would you suggest Direct Burial cable for doing aerials? I have to do a run of about 75' and I will be running 2 x Siamese, 1 x 18/2, 1 x 22/4. This is for 2 cameras and an access control reader and I/O cables. Instead of buying 22AWG for I/O for one area I will just use the 18/2 I already got... Anyhow. DO you think standard cable will work or should I go Direct Burial. Something about UV exposure I'm not sure about.

 

The electrician already cam in and put the guide wire and a riser pole specially for this project.

 

Thanks

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For Aerial work I always used RG59 WITH 17AWG STEEL MESSENGER (Outdoor rated/gas injected foam polyethylene) there is also RG6U with a 18 AWG solid copper core 95% braid a WITH 16 AWG STEEL MESSENGER on the market... pulled parallel with the core under a polyvinyl chloride jacket .... ask your electrician for details on rigging and info on grounding a mast .... outside entry considerations etc (use outdoor rated only-Polyethylene recommended for all outdoor whereever cable is exposed to moisture, sunlight and any abrasion....do not use indoor rated cable for aerial or DB or even in conduit ...the electrical and mechanical characteristics will fail over time and haunt you later....

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Thanks Lolo Wolf

 

Do you go through a distributor for your cable? Can you PM me with your source please? I can find standard RG59 with messenger but none with Siamese and messenger if that's the case what are you doing on the power side?

 

Thanks

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The aerial work Ive done always powered local at the pole due to long outdoor runs but last remembered Belden has a product for your application as well check with: www.midsouthelectronics.com(478299, RG59 20BC 95%BC. AERIAL. WITH 17AWG STEEL MESSENGER. FOR AERIAL USE, 20 BC, N/A, 0.236" X 0.370", 1000FT REEL[06], BLACK[08]....1000ft-500ft reels/box not cheap but perhaps you can search out a custom cut there are some china Siamese outdoor with messenger Ive seen on the web but another source perhaps contact Olympic www.olympicwire.com Check with electrical supply (not big box stores) for your span/drop clamps, S clips, strain reliefs, galvanized deadends and anyother suspension hardware you may need, are you going to be inspected? If so talk to your electrician bout local codes for your area. Im slow these days due to health considerations but Northen Video has always helped me source products in the past. Good Luck

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We can't do wireless because of an access control reader being installed as well.

 

I am interested in how you protect for lightning. We had electrician install two masts and they installed a messenger wire from one building to the next. All we will need to do is lash the cable up there.

 

Should we just install surge protectors on the video cable? How would I protect the access control cable as well? I got power running over these cables as well for the access control and the cameras.

 

I am meeting up with the electrician this week again as well because I need for him to run some conduit for me. The low voltage cables will be installed in a Class 2 hazardous location so conduit is required so I am leaving that all to the electrician.

 

Thanks.

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Electrical equip class II location -Flammable dust - calls for a NEMA 9 dust-ignition-proof enclosure... if you are terminating to a pwr supply within the hazardous location (combustible dust present or may be suspended in the air) always restrict the use of unapproved equipment in your hazardous location (aside from hot work permits- when it is determined there is no hazard currently present and that conditions will not change while the permit is in effect - make sure your electrican is knowledgeable working within these class rated locations. Double check all equipment after construction (are you working from a approved plan? If so make sure the new equipment that was installed is to plan-spec for the area and properly labeled and periodically inspect to ensure that you have a closed electrical system. A commercial/industrial application within a hazardous location needs special attention to detail for safety. In so far as lighting protection, this topic has been addressed often on the forum in the past, in my opinion soil type, building materials, service type, lightning zone are key to designing a system

that can be signed off on, there are several expert lighting protection services in the field... but for camera and related devices entering structure bonding is key, there are too many considerations to go into depth here and really pays to source a expert. There are many arguments some Ive read here on the forum with bleeding charge vrs diverting stikes .... I do know from past tower (line HV and DOT related traffic jobs and battery rooms sub-station contracts for rail transit above and undergroung) we always followed design paper involving air terminals as well Ufer Ground systems.... there are codes for conductors and be wary of quick answers from people telling you the definitive Lighting protection answer... over the years Ive seen em all....diys shoving rods and playin with installs that can do more damage than protection.

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All 6 wires will be coming down the mast and terminating is a box where the conduit will then go to a stationary camera, a PTZ and a box designated for a the access control reader and a stop switch. No power will be brought in from the building, which by the way is a diesel fuel building. The building was built around the fuel tank and it has ventilation like crazy.

 

So any how on to the wires...

 

- 2 x 18/2 wires for the stop switch and one one set from the dry contacts in the access control panel.

 

- 2 x Siamese

 

- 1 x Cat 5

 

- 1 x Belden 8723 (equivalent) two individual shielded pairs for the reader

 

All cables are direct burial stuff to with stand the elements. I will be lashing the cables to a messenger cable that is already sturng up by the electrician.

 

I need a method of grounding all this. I can put surge protectors on the RG59 cables and the questions here is should I put them on both ends?

 

I'm not sure about the 24VAC power for the cameras, how should I protect these so they don't fry a camera or the power supply.

 

How about the Cat 5 control wire for the PTZ?

 

How about the access control lines?

 

I REALLY wish the customer would have listened to me when I said to put this stuff underground through a conduit. Now we will have all these issues to contend with. I know, the odds are probably low the the line will be struck but the risk is still there. I would at least like to have some safeguards in place.

 

Thanks.

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sorry for the late reply.... some quick thoughts- surge-protected at the building entry point (outside plant common with telco apps LV etc)- ground bond connector slips under the jacket/ shield and tightend down with a bolt, due to your Hazardous local- special attention needs to be made at entry not to envoke any possible ignition point thru arc by improper wire or splice points as well special attention to proper shielding LV wiring (signal,etc) can be problematic in noise production you may need additonal termination gear to eliminate cross talk and possible interference.... your situation calls for a real evaluation on site for all protection...libility as well safety due to the possible explosive/ignition factors in your local and would be well worth your while to consult a certified source. I am not one to just answer with NEC reads but there are so many varibles pertaining to your application and codes do need to be followed...how they can be interpreted is a argument often based on inspection or local. the only defintive remark I would make is that bonding should be done to the existing building electrode system. I can tell you this Ive replaced pole cams that were so called bullet proof with lighting protection, bonding, surge protected as well UPS, AVR, all the works.... sucessful with minor brown and surge but have come to the conclusion real world nothing is bullet proof - hit or miss..... I am not a lighting expert nor do I profess to be one but have worked around several systems in the field designed by experts and the results with protection due to lighting damage often were limited to certain degrees and some very reliable but Ive seen some vaporized damage to not only devices but complete housings and enclosures, building mechanical etc due to lighting..... in regard to your "lashing" the cable there are percise methods for your aerial application, really specific methods (hardware, spaceing, etc.) not trying to give you a hard time or lecture but it pays to do it right and follow the codes such work done improper can bite and haunt you later big time if there is a problem. good luck. regards and best of health.

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3RDIGLBL wrote: I REALLY wish the customer would have listened to me when I said to put this stuff underground through a conduit. Now we will have all these issues to contend with. I know, the odds are probably low the the line will be struck but the risk is still there. I would at least like to have some safeguards in place.

 

- underground or above both aerial and buried considered- do not get a false sense of safety if you had used buried conduit - - Above-ground are shown to be more at risk from transient-induced voltages. a backflashover from a tower in the vicinity to a conduit is possible - Conductive coupling can take place at the same time as inductive and capacitive coupling. Backflashovers are shown to be a important consideration when designing- Lightning wants to get to ground by the easiest method available. If allowed to advance with no control mechanism through a structure, it may move from grounded system to grounded system “jumpingâ€

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3RDIGLBL wrote: "which by the way is a diesel fuel building" Sir in general, "common" diesel is not considered flammable or combustible (flash points etc) and from what I remember electrical area classification is unnecessary however Any local department, that has power to enforce regulation over your operation (an AHJ) often will not always agree and interpret things differnt. This is why I stated you should ask your electrician bout any local/regional codes pertaining to your install(municipal, county or other factors) The facility can be forced to answer to OSHA, Fire Marshall, even a insurance provider. any of these persons may deem specific methods or demand a a classification. Your earlier post stated a class 2 local....I use the NEC as a refrence and Diesel is not listed as class 2 "The second type of hazard listed by the National Electrical Code are those areas made hazardous by the presence of combustible dust. These are referred to in the Code as "Class II Locations." Finely pulverized material, suspended in the atmosphere, Some typical Class II locations are:

Grain elevators;

Flour and feed mills;

Plants that manufacture, use or store magnesium or aluminum powders;

Producers of plastics, medicines and fireworks;

Producers of starch or candies;

Spice-grinding plants, sugar plants and cocoa plants; and

Coal preparation plants and other carbon handling or processing area" heres a good read on Hazardous (Classified) Locations pertaining to electrical work etc http://www.osha.gov/doc/outreachtraining/htmlfiles/hazloc.html If I am wrong please correct me.... Regards

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You know I am with you on this one. I spoke to the electrician and I told him this is not listed as a class 2 per the NEC. I showed him the NEC 2008 book but for some reason he says it is. Who am I to argue. The customer is paying the elctrician to run the conduit so whatever, let the customer pay.

 

I spoke to a couple different electricians and an engineer for a phone company about the grounding part of my install and both said don't bother. They said if there is a direct lightning strike nothing with save your equipment. THe phone guy said they have been trying to fight mothernature in this area forever. Although they can minimize damage they can not prevent it when you are talking 1000's of volts of a direct strike lightning bolt. He said I'll be wasting money for nothing. The direct strike would jump any type of suppression I put in there.

 

He said use UPS systems for line fluctuations and ground any of the equipment per the manufacturer but that is all that will really be needed.

 

Comments on this? What have your experiences been especially with coax surge protectors that are in line with the video signal. Is there any proof that these work or is this just a bunch of marketing hoopla??

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Your added info aids me in understanding the situation... As I stated earlier lightning let alone DIRECT strike involves a costly design process that has to be built to each unique site, and frankly in your case with the set of factors (liability, payment contract etc) just make sure you cover yourself IN WRITING and give em what they want. In so far as your part (devices) in this matter UPS along with a AVR I prefer a combo for small set ups there are some decent ones (have used Tripp-lite gear single AVRs and their Heavy Isolator units as well I have stopped using the APC line years ago after some quality issues but thats another conversation...use some of the Cybe-Power units -have done me right ....have several PP2200SWRM2U units in racks and never had to touch em calls for a Nema 5.... the smaller cyber with AVR now called "GreenPower" have worked well for me as well Reliable and your attention to power condition will insure a install less problematic job for sure, most of the call backs Ive encountered in work not done by me is often related to power or mechanical issues (cable placement, termination etc) If the electrician on site is responsible for the AC and conduit, poles masts etc then sounds to me that you are good to go....any inline device for surge protection that does not envolve a hard wired ground I have little faith in even for minor disturbances I have used some of the DITEK line of coax devices with the ground lead. Seems to be that the advice you recieved from your other sources sounds grounded to me...no pun intened. Just make sure that THEIR end (the prime on the JOB) doesnt screw up your end if you know what I mean....nothing worse than a blame game after or before the fact to give you a headache. I am loaded up with CHEMO jus now and thinking back which often I do at times like this trying to take my mind off of it over all the years past back east in Highway and heavy tunnel work and all the BS that used to go down with just tryin to get a job done right. done safe and with pride its no wonder today everything is jus fallin part. Good luck Sir and hope all goes well for you and best of health....in the long run thats really all that matters along with family.

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