Saturday, August 20, 2022

Oh, The Thrills

      Yesterday afternoon, after doing what work I could from home and preparing to leave, I found myself ill with the sort of gastrointestinal unpleasantness that arrives with little warning and leaves you wondering if it will strike again.

      So I unpacked and found more work to do.  Early evening, visiting the smallest room, I flipped the light switch and the light came on bright, flickered, and dropped to a dim glow.  Rats, dead bulb.  I turned it off -- and the light stayed on.  Switch didn't feel right, either.  Floppy.  The fan and its switch worked; the GFCI on the same circuit was happy.   I made my way to the basement and killed the breaker.

      The electrical in that room was one of the few things I hired done when I was moving in here at Roseholme Cottage.  It needed an exhaust fan and the only convenience outlet was in the light over the lavatory, controlled by the same small pull-string switch as the light.  Inconvenient, not on a GFCI, and shring the same branch of the same 1920-vintage wiring* as the overhead lights in the "private" part of the house.  So, a new circuit from the breaker box and a nice quad box to one side of the medicine chest, with a protected receptacle and dual switches for the fan and light.  That was fifteen years ago.  The little switches that fit the footprint of a duplex plug are typically marginal and apparently, the bulb failure had taken one out.

      I felt well enough to make a closing-time dash to the home-supply store and came home with a pair of replacement switches, ivory rather than white, with a new wall plate to match.  But I decided to wait for daylight to replace them.

      This morning was a reminder of why my (limited) experience with commercial power wiring isn't ideal prep for residential wiring.  At work, our stuff is in conduit, nearly always stranded wire, and we use crimp-on lugs, generous service loops and finish with a wrap of black tape around the device; you can remove them from the box hot (but you shouldn't) and everything is easy to get to.  The residential electrician has a tougher time: solid wire is standard, the boxes can be no deeper than the wall space, and there's no room to cram much extra wire behind the receptacles and switches.  None of it is arranged for convenient servicing.  There's a reason residential electrical work is rarely low-priced: you're paying for a highly specialized set of skills and an uncommon degree of patience.

      The circuit was still off and a non-contact voltage indicator confirmed it.†  I gathered up my gumption, pulled the plate, unscrewed the switches and pulled them out.  It became clear the the GFCI had to come out, too, in order to get to all the connections.  Much fussing and fighting with solid wire followed, along with peering at clearances as I put it back together.  Finally I had Tam watch the thing while I cycled power on and off quickly -- okay -- and then turned it on.  The bulb was still bad, but at least it shut off with the switch off.  A new bulb fixed the light, the new plate got Dymo labels for function and breaker number and I was reminded once more that the legend on the breaker box is more like mythology than documentation.
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* At this point, the overhead lighting, the outdoor/porch lights, the radon fan and a floor lamp in the living room are the only things left on the old tube-and-knob/flex.  All the lights on it that we use are low-draw CFL or LED.  The wall outlets are all modern plastic-sheathed 14/2 plus ground back to the breaker box, but the previous owner just refed the original four lighting circuits when he updated the electrical.  I get it; replacing tube and knob wiring to switches and receptacles is a lot of work for no visible change, but it's eventually going to have to get done.  Modern bulbs literally take a lot of load off of it and as long as the 1920s electricians used the right flux when they soldered -- well, there's a degree of wishful thinking and thin resources in keeping it in service.   
 
† This is the cheapest $8.50 or less you'll ever spend.  They tend to the occasional false positive (check with a meter!) but these little voltage probes will tell you in a hurry what's safe to touch -- or not.  Worth owning if you do any AC power work, and worth storing with batteries out so it won't be corroded to uselessness the next time you need it.  Ask me how I know....

8 comments:

RandyGC said...

Never worked with the non contact indicator you used.

So, is there any advantage to one of those over a multi-meter that does AC (of which I have way too many around here)? (i.e. worth buying even with multi-meters available?)

Most (99%) of my electrical work these days is 12V DC or less

Roberta X said...

Not at 12 Volts, no. Most of them won't register anything under 50 V, AC. The advantage is that you can poke the insulated snout of one of those "sniffers" into crowded 120/240 VAC wiring where a meter could easily make contact between a hot lead and the electrical box. Most have a light and a beep, so you can keep your eyes on what you're doing instead of having to read a meter.

It's a safety tool. In a house like mine, where the vagaries of tube and knob wiring can make everything read a little "hot," I sometimes have to double-check with a DVM, but the non-contact indicator is still useful. At work, I wouldn't be without one -- there are at least two circuits in every rack, usually one on the UPS, so the outlet strips are being fed from different breaker boxes in different locations. It's easy to miss one and get a nasty surprise. Since I came up with the way we wire up racks (staggered outlet strips, so the receptacles are never side by side, and a very controlled, deliberate, consistent way of connecting all the grounds for the rack and power ground are absolutely at the same potential, among other things), I'm kind of the Den Mother for doing such work -- and I have tried to tech careful habits, so I don't have to give anyone CPR.

Bob said...

A couple of observartions:

Working on residential electrical systems is a piece of cake. Just need to get used to it and it's easy.

Knob and tube is really a fine system; no overheating problems or fire risks; tough to work with but back in those days labor was cheap. No need to replace it.

You're right about phony breaker lists. First thing I do in a new house is make a detailed, time consuming chart of *every* fixture in the house and which breaker it goes to. Then post it near the breaker box.

I'm confused by the GFCI and other protection devices. What do new installations require?

JC said...

Oh dear Lord, I can't tell you how many meters I have. Lots. One's a clamp on Volt Ohm Amp meter with non-contact skillset. Not as nice as my EDC Amprobes with the wheel to switch function/scale and that needle that goes up and down. (I'm an analogue guy) Residential wiring can be somewhat...perplexing (I know you have a pg-13 policy). I opened a jbox the other day, there were 3 different circuits running through a single receptacle box. 2 different breakers, one 120 and one 240 that had been split into two 120s. Still tied at the load center, of course. Those twin switches are neat, though.

Roberta X said...

Bob, I'm not up on current Code and the various requirements. As a general rule -- this is talk, not professional advice -- kitchens, baths and places that might become damp (outdoors, basements, laundry rooms) get GFCIs, with some rules for proximity to sinks and the like. Bedrooms get arc-fault protection, which is supposed to help keep your bedding from burning up if the electric blanket (etc.) goes haywire. But I am years out of date, I rarely work on residential stuff, local rules vary and you should always seek up-to-date information from people who work with it. In most of the U. S., old installations are "grandfathered" and can remain; there's a tradeoff between safety improvement and placing undue burdens on property owners.

GFCIs are lifesavers and widespread use has made them relatively inexpensive. They can be retrofitted to many existing installations. It's generally worth buying quality receptacles, GFCI or not. You can use fifty-cent Contractor-grade stuff, but it will wear out fast and it's usually a pain to work with. Specification-grade hardware will last for decades at little additional cost -- and it's got better warranties, too. (There's a limit to spending more for better results: Hospital-grade, as I understand it, gets you very little more other than a lot of it is clear so you can see spills and other trouble, but the increase in price can be substantial.)

RandyGC said...

Thanks Roberta.

I may see what they cost next time I'm someplace that sells tools. Never know when I might be doing something out the ordinary.

Another advantage of GFCIs: Our house was built in the 1950's with no third ground wire to most of the outlets. Many of our 2 plug receptacles were worn out and would not physically hold a plug.

This summer, among some other work, we had our electrician replace several of them with GFCIs. Not required by code outside the bathrooms and kitchen, but safer from a grounding point of view, and I now have a bunch of unneeded adaptors. Also a LOT cheaper than running new romex to each one.

Glenn Kelley said...

Thanks for the prompt.I just went and checked the batteries on my tester

grich said...

The comment about residential wiring being a piece of cake is not quite true. If unqualified people have tampered with things, there could be lots of time bombs hidden in the walls. It's frustrating to have a circuit quit working and find out a splice failed in a box you don't know exists because someone buried it behind drywall. Or the splice is hanging in thin air.

My house has a basement finished by the previous owner. Grounds were cut back (who needs 'em?), and hot and neutral were reversed on all outlets. The garage had the same issues, and I found three buried junction boxes in the basement ceiling. I got to fix all of that. The garage was fun...it's in rodent-proof EMT salvaged from the demo of our DTV UHF transition site. You bet I used stranded wire for that. That's also where spec-grade devices come in handy...the back-wire clamps are perfect for stranded wire. I eschewed the 50-cent devices years ago.