| I have a couple of sightings of the HV overhead arcing, but my involvement with it was limited to just watching it, so all i can tell was "sparks shot and lights went out"
And i have stories which unfolded in front of me as i was working on the installations myself. There were no arcs, explosions or high voltages in those stories (just plain 230V), but those fit well the subject here
For today - the first one - From 2019
An apartment building with 8 floors, of which one is an above-ground basement, one (few floors higher) is the main entrance lobby, and the other 6 are apartments. (The building is built on the side of a steep hill, with the entrance from the high side. Some flats are above and some below the lobby, while they all have windows to the sides and to the side facing downhill). It was built around 1970, typical for then small town low budget construction
The lobby and stairs lighting in this building have not worked in ages (last time i recall any of that working was in the 90s, when some friend of my parents lived there), the electricity for the common areas lighting was cut off for unpaid bills years ago, and many fixtures were since then vandalised
The main population in this building was eldery and relatively poor people, most of which also from soviet background, which dont tend to complain about anything. They made up with the fact they have no lighting in the stairs and have not looked into repairing it, going in and out of their flats with a flashlight
One night some granny there slipped on the stairs and broke an arm, and then word began to spread. Eventually i heard about it and contacted them. Long story short, they got the message at last (that they need lighting and have to do something about it), but they were not prepared for the costs - Both the one-time fee to reconnect the power at the meter by the power company, and the electricity bills (after some individual tenants who used to live there would stick the lighting switch to be permanently pressed, while chilling for hours in the lobby. I can imagine contacting those tenants to collect the money would not be warmly welcomed either)
Quick assessment by me :
1. (8 floors + 3 additional lamps in lobby + 3 additional lamps in the downstairs lobby near the basement) * 4W LED filament lamps = 56W
2. 56W * 24h * 30d * 0.6ILS/kWh = 24 ILS/month (approx $7/month) total cost of electricity used if the lighting would be on permanently. (Back then, when the power was unpaid and cut, it would be 10..15x that with 40..60W Incandescents). Divided by 12 flats thats $0.5/flat/month
3. Probably under 3 ILS/month (approx $1/month) if they act like civilised people and don't stick the buttons. they won't even bother walking collecting the money from the tenants...
4. Don't need the power company and their fees, let's just reconnect the entire lighting circuit to be fed from one of the flats
5. To prove point 3 to the tenant from which i took the power, i can add a small kWh meter just to measure the kWh draw for this installation
Equipped with some replacement "meltlights" (cheap plastic enclosed light fittings with E27 socket, notorious for melting if used with Incandescents) and push buttons to replace all the vandalised ones, LED lamps, spare circuit breaker, timer module and some wire, i went there to start off
I removed and isolated the customer side wiring between the disconnected meter and the box from which the supply is feeding into the common area circuits. In its place, i took power from a flat which volunteered to provide it (another old lady), adding a separate breaker in that flat's board
I went through all floors, replacing vandalised light fittings and switches
I pulled the switch in the basement floor (it was still usable, but i had a feeling that i better replace it). Tested the wires in the box behind it with my meter, and they were LIVE!!! - in a circuit which was supposedly dead for many years
Tracing the live wire found the origin of the power on it :
It was pulled in the conduit running along the staircase circuit between the basement floor and one of the "lower" apartment floors. Then it was drilled from the switch box there, through the wall, into the electrical board enclosure of the flat on that floor. That happened to be the flat of the lady who broke an arm
The board was locked. I knocked on the door and asked for the key
Opened the door of the enclosure and found that the wire is sticking into that lady's breaker panel
I opened her breaker panel, and found out an interesting feat : The RCD (GFCI) was bypassed, it was still there and still had power connected to it (so it tripped when TEST pressed), but the power for the row of breakers of the flat, as well as the rogue wire (taken directly from the main) was connected bypassing the RCD
My talk with the lady :
"I opened your board enclosure to find from where i am getting power downstairs, when it is not supposed to have any power now. Here is evidence that there is ongoing power theft from your flat. In addition and more importantly, they bypassed the device which is supposed to protect you from electrocution, so it won't be shutting down whatever bad wiring they have down there. This puts you in danger of electrocution in your apartment. This wire must be disconnected and your protection restored immediately"
"Is this why i am getting electric shocks from the kitchen appliances ?"
"This means you have at least one additonal problem in your flat, which makes it an immediate danger requiring immediate attention. First of all this means you have no ground, and it might or might not mean that you have a failing appliance which already is passing voltage to metal bodies of appliances you are touching"
(Many appliances contain capacitors between Line and Earth as part of an EMI filter, and if main Earth is not connected, they pass some current that may lead to a mild shock feeling. In this house there is Earth in the sockets from construction. This means, that if the main Earth is disconnected, the appliances are still connected to each other, so the shock you may get from touching any of them is the sum of currents from capacitors in all of them. This is still without any actual failing appliance. If a failing appliance is present, anything up to and including full low impedance line may be present on the apppliance enclosures)
I gave this lady a full inspection of her flat for free, and corrected a few discovered issues :
- The rogue wire was disconnected, and RCD connected back as should be
- Main Earth connection for the flat was severed. Originally in those old houses it is T-T system, with the source of Earth being the cold water pipe. Over the years plumbers have replaced burst pipe fittings in the basement with plastic fittings, but have not reconnected the Earth to the main pipe coming from the ground. I connected a new Earth wire, running it in external conduit from her breaker box to the water main
- No failed appliances were found. It was indeed just capacitor leakage, but summed from multiple appliances
- She had a space heater in the bathroom (the proper type for bathroom use, mounted on the wall, with built in pull cord switch) that was installed at some point (it is an addition, there is no wiring provided for such heater from the original wiring of the flat). The installers pulled the wiring for the heater from a connection box on the other side of the wall (This is a box high on the wall, just below the ceiling, closed with a flat plastic cover. In it are splices of the wiring for that room). They made awful job splicing their new wire to the existing ones there, which resulted in a connection that was heating to the temperatures of glow when the heater was turned on. The remains of a wire nut, sticking on some bare wires which insulation crumbled long ago, not shorting to anything just by luck, was melted right through the cover of that box and into the back of a clothes and bed sheets cabinet (with its back made of thin sheet of like pressed wood-cardboard material), which was standing against that wall in the room. Few more hours with that space heater and the back of that cabinet would be set on fire, possibly a smoldering fire which would take a few more hours (till later in the night) to develop into flames
I told her karma is a b-tch. Her broken hand might have well saved her from death by electrocution or fire
The rest of the repair of the lighting was relatively straightforward, some light fittings and switches had to be replaced because they were vandalised, and some wiring had to be replaced because it was cooked by Incandescent lamps in the past and its insulation was crumbling
As i flipped on the power and started screwing lamps into the sockets of the luminaires, moving with the ladder from top to bottom of the staircase (using the spill light from the floor above to see what i am doing in the floor below, ie. open the luminaire - 3 screws, and insert the lamp), a lamp in the floor above me extinguished and it became darker (still some light from 2 floors above reaching, so i could finish that floor)
I go there to see the LED filament lamp is out. (The lamps in the floors above still work, so it is not the power that went out). I have some spare lamps with me (because i bought 2 complete boxes and not exactly the needed lamps) so i just go back up there with the ladder and relamp it. As i unscrew the lamp from the socket i notice that the lamp base is abnormally hot
As i return downstairs (with one lamp less), the lamp there flickers wildly for a few seconds and after that remains in a steady dim state, with a visible dead chip in one of the 4 filaments. I relamp that one too and continue to the basement
By the time i finished lamping up the entire circuit, another lamp in the upstairs lobby died in the "lamp out completely, base scorching hot" mode
I have used lamps from a manufacturer i generally regard as a good quality one. It is not one of the big brand names, it is not expensive, it is made in China, but really i have had no trouble with this brand before, and no trouble since, and regard them as a generally good quality brand to this day
Assuming that it might have been a bad batch of lamps (and that the entire stock in the shop may be from this batch), i go to the shop and get another box of other lamps. (I was mildly interested in putting the bad lamps to some tests, so was not going to request replacement anyway). Same manufacturer, same 4W LED filaments, but the ones i got at first were C35 candle shape, and now i took the G45 globe shape - assuming that they gotta be a different batch so likely to be ok
Nope. The next day i came (to find a few more lamps dead, there were some of either "dim lighting and one of the chips is out" mode, and "lamp out and base hot" mode) and relamped those too. The next day a couple more were out, including from the yesterday globes
I kept replacing lamps for another day (now using lamps from both from the candles and globes), and seems that i did indeed weed out all the bad lamps. The most i have replaced there was 4 times in the same luminaire with a day or two between lamps, but the 4th lamp lasted ever since. I have come months later to revisit out of curiosity, and all lamps were still ok. By the way, the kWh meter was reading some single digit figure kWh
Some of the bad lamps had visible cracks in the filaments (only after use, not when they were new), and in some the phosphor coating might have started curling back from the cracked spot. I think those might have been leaked, having air inside instead of the Helium, or just defective filaments. I have not examined further the "hot base" ones due to lack of time, but i think it might have been a shorted capacitor parallel to the filament array (ie. after the driver output). I still have somewhere samples from both types of the bad lamps
I have not been in that area for a while, but last i recall (near the beginning of the Oct 2023 war, when i was in a team of volunteers inspecting air raid shelters) the lighting there still worked
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