I have a QuestionQuestion. Can phone lines, fire alarm cables, and 120-240 cables be put together in an outdoor back box?
ReplyBesides the legal aspects, fire and safety issues, there's the interference problem.
The voltages and currents from the 120-240 volt cables will be cross-talking to the low voltage cables. How much cross talk is produced will be affected by the actual currents in the high voltage cable, how tight they are to the low voltage cables, and the distance they are running together. The tolerance to this interference is a great issue, and depends on the signals used in the low voltage cable.
Unless you are prepared for major problems from all these issues down the road, I wouldn't recommend it under any circumstances.
You are right about keeping power and control wires separated -- Had a fire alarm system many years ago that had 24 volt smoke detector wires and 208 volt fan shut down wires in the same conduit: 250' run in the dirt under the bottom slab of a building. Read More
Are As-Built Drawings Available When Needed? -- When available, as-built drawings are used by architects and engineers for remodeling or for designing new additions to... Read More
Can Low Tech Follow-the-Wire Help Troubleshoot? -- Someone once said "Experience is something you gain when things go wrong." Well, wiring issues are things that have gone wrong, and a lot of experience... Read More
Can Fire Alarm Fiber be Run in the Same Conduit as BMS? -- Can fire fiber riser be run in the same riser conduit with BMS? We only have one riser conduit for both. The engineers are saying we need two separate conduits, your thoughts? Read More