Replacing light fixture, old wiring - what's going on?
beckington
6 years ago
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Comments (7)
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Recessed Lighting - replacing old square recessed lights
Comments (14)davidr - you are correct in that new cans will have a tighter light distribution than the old squares. The reason for the switch is that one of the old squares flickers and spits - so that there is a wiring or fitting problem there. Accordingly I have removed the bulb on that one unit. I thought that if I am going to replace one unit that I might as well replace all of them at the same time or it might not look good. In addition an electrician told me that the old square lights are "dangerous" as they dont have thermal cut-offs and are thus fire hazards.......See Morereplacing k&t light fixture wiring
Comments (4)Civ, from my electrical book, I don't think you can avoid making a hole--but it doesn't have to be big--a couple inches should do it. Sort of confused by the statement 'no attic access'...if so, how are you adding the insulation? In my bedroom, they added a switch for the light by using wire channel--metal 'tubes' which are surface mounted to the wall/ceiling--not a great look, but it can be painted to match the room. The second bedroom has no light, but the electric outlets were run the same way just above the baseboards....See Moreold braided wire - alternative to replacement?
Comments (4)I shut off my main switch and looked in the box to see what this would entail today. Under the nasty looking cloth covering, the insulation of my old wires is definitely plastic, and it looks and feels perfectly sound. So it is the latter type below and this is probably why my home inspector said it was perfectly safe. I'm not going to do the upgrade to AFCIs. From that thread: I've come across two types of NM cable from the 50s. Very early stuff with cloth covered individual conductors, and the more modern cloth-sheathed romex where the individual conductors are insulated with a thermoplastic. The more modern type (with thermoplastic individual conductors) is very widespread in most housing applications from late 50s and 60s and poses no safety hazards and can be left in service. However, the earlier romex (as the first post described) does pose more of a concern. The cloth insulation gets very brittle, especially in lighting boxes. I would make this cables replacement a project soon....See MoreReplacing light fixture, old wires
Comments (3)To re-iterate what btharmy said, the old BX has no bonding strip and although it may test as being grounded, the resistance of this grounding path will vary greatly depending on the distance of the run and the integrity of the connectors. Once the resistance reaches a level high enough to reduce the flow of fault current to a level below the fuse or circuit breaker rating and a ground fault occurs, the armor will just sit there energized, along with anything else connected to it. Depending on the resistance it can turn into a heating element and get hot enough to start fires, as the high resistance will prevent the fuse from blowing but can allow enough current to flow to create a heater. For this reason I consider the old BX to be more dangerous than knob & tube, especially as it ages and gets monkeyed with. Incidentally if you read the label on any new UL approved lighting fixture you will see that it forbids installation on older building wire due to it's insufficient temperature rating. This post was edited by joefixit2 on Sun, Jan 18, 15 at 9:46...See Morebeckington
6 years agogreg_2015
6 years agoVith
6 years agolast modified: 6 years agobeckington
6 years agoDavidR
6 years ago
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