Extremely loud pop inside apartment building, half the outlets (on the same curcuit) wont work in my apartment

Question

There was an extremely loud pop somewhere above my apartment in my building. Over the next few minutes a strong smell started coming through the AC, random lights would flicker then cut out, and items would stop working all together (night lights, child monitor etc.). this happened throughout the building. i was told it was a power outage by our power company, however, i have never been in an outage where random outlets would work/not work that were on the same circuit in the breaker box. some lights/outlets would be constantly browning out while others were not (also on the same circuit). resetting breakers did nothing, resetting outlets did nothing. i unplugged everything and waited outside until the issues were resolved. everything started to work again about 2 hours later.

I was just curious if i should be worried about anything because the housing authority had no answers and the power company just said it was a power outage. But there was a very loud pop (borderline small explosion) sound and a burning smell in my AC. thanks for any help

Answer 1

Did you happen to notice if the transformer on the utility pole nearest to your house now looks shiny and brand new? From your description, it sounds like it blew. When this happens, for a few moments the voltage coming into your house could theoretically be anything (up to the high voltage side supply, usually several kilovolts), as the various windings within the transformer melt and short together. Given that, it would be wise to check that all your devices are still functioning properly. If not, check to see if your homeowners or renters insurance (if any) covers this.

You mentioned that some outlets were working fine while others were browning out -- how did you determine that? If you're just going by which devices stopped working or dimmed/slowed down, that's not a reliable indicator, since many modern electronics with switching power supplies will continue functioning even on very reduced voltages, but other devices will not.

Answer 2

My initial assumption was also an outside transformer. However, if you did not see one being repaired, combined with the fact that you mentioned that this is a large complex and you heard/smelled it, it could have been a transformer or upstream breaker on-site. Based on what you described, light bulbs dimming, electronics failing completely, it sounds like the root cause would be reduced voltage. Electronics with decent transformers can handle small power swings but will quickly fail if they cannot provide the minimum voltage for the circuit. LED's and CFL's have drivers which will need a minimum voltage to function at all. On the other hand incandescent light bulbs can run (poorly) on only a few volts.

The fact that the noise sounded like it was coming from upstairs weird. My best guess is one of your neighbors was drawing a lot of current which somehow bypassed the main, which caused a leg of a transformer to fail.

Here is one theory, but it is only one possibility, but definitely not the only one. I used to live in a Philly row home in a shady neighborhood and something very similar happened twice while I lived there. The second time I found out what happened when a house 4 doors down caught on fire. The junkies were attempting to "jump the box" meaning removing the meter from the socket and bridge the gap to get free power. The fact that you didn't get good answers from the housing authority supports this, but usually this is only possible in places where meters are located in-near the home and not on the ground floor in a common area.

Answer 3

It's exactly what it says on the tin, a power outage. Since you are in an apartment complex, it's not your job to get the power company out, but you are welcome to call them.

However in the US, power comes in two "poles" and a neutral. What has gone out matters.

Check large 240V loads like water heater, range, and installed air conditioner. If they work great, you have lost neutral. It is very important you unplug all 120V loads at once, and not plug them in again until power is restored. They will have random voltages between 0V and 240V, and that will fry equipment!

If the appliance barely works or doesn't work, and turning on a large appliance makes your dead outlets come back to life, then you lost a "pole". Turn off the 240V appliances and and do not use them. Half your 120V appliances will now be out. They will come back when power comes back.