I have several reasons to believe somebody is stealing my power. I decided to flip all the breakers… and behold my next door neighbor's exterior garage light turns off then comes back on but significantly dimmer. Now since I can't see the front from the back of my house where the breaker is, I had a friend help me have eyes in both places by posting up front or flipping the breaker and vice versa. We both saw this light do the exact same thing.
The questionable part about it is that it only behaves this way concurrently to my breaker when this light is super bright, white. It doesn't even flicker when dimmed low yellow. It is NOT a motion light, and before all of this I never paid enough attention to know if the fluctuation in brightness is abnormal but I want to say I thought it was usually if not always very bright.
Now maybe we tipped the neighbor… but the last time we attempted this experiment, the light literally flipped itself off and went to dim seconds before we could turn the breaker. Then it stayed dim as far as I know for the rest of that night. The very next day the power company cut my line because I haven't paid up the nearly $2,000 due now. (2 months usage with only 2 people).
My property consists of two detached houses on the same lot, separate addresses and same meter. I purchased 2 years ago, live in one, rent the other… I evicted the tenants in the front house because they couldn't pay for all of the energy I thought they were using. Then my first bill without them was more than double and has been nothing but random since.
I don't want to start a problem with my neighbor unnecessarily. How can I determine if the power usage is due to my neighbor?
Best Answer
You have a tough bit of detective work to do, but it should be possible. The good news is a very large load is likely to be a continuous load, so it shouldn't be too hard to catch.
First check for weird outside wires.
The usual drill with pot growers is to bury Romex (NM) cable just enough to conceal it. This shabby workmanship is usually fairly easy to spot. Proper underground cable is at least 12" deep, rigid conduit can be 6" but that's because you won't damage it with a shovel.
A sneaky cable would explain all this even if they took away their grow lights. (you have inspected the unit, yes?) Imagine they were stealing power from the neighbor, then also stole it from you but hooked it up backwards. It would be a dead short, limited by the long wire run, and that might be enough to not trip the breaker.
OK, no luck?
Next, get educated.
I know some people don't like learning and don't want to be seen as smart. But frankly, the alternative is pretty expensive. Upside, this is a big enough deal you can afford a few toys to make learning easier.
Once you are able to easily read your instantaneous watts (e.g. at the meter), you can try flipping off one breaker at a time and try to narrow it down to one breaker. If your two units have separate panels but are fed off one meter, you may be able to use a clamp ammeter to measure both main hots (one at a time) to see which house is the source of it.
If an answer doesn't become obvious at this point, you'll need a more methodical approach.
Map your circuits
This is tedious but very useful to know. You know about all your hardwired loads (lights, oven etc.), get some dollar store night lights for testing receptacles. Shut off one breaker at a time and see what got turned off. Mark the service panel with what things that breaker controls, and mark each device, switch or outlet with the breaker number.
Next, use the Kill-a-Watt to measure the actual power draw of everything that plugs into a receptacle. I have been known to measure fixed loads also, by opening up the box and using a stinger extension cord. You cannot measure 240V loads with a Kill-a-Watt, but then you don't have to - 240V loads have nameplate labels which state their power usage. You just have to figure how often (percentage of time) the big load is on. By now you should have a notebook or excel of each of the circuits and the Kill-a-Watt power usage of each of the devices on that circuit.
Look for anomalies
Now put the clamp ammeter on each of the "hots" coming out of a breaker. Compare that to the Kill-a-Watt data from your known loads on that circuit. It can help to just turn those off while you're measuring. The goal is to account for all the power exiting every breaker.
For 240V loads, measure both hots separately. A significant difference in amps should raise alarm bells. Dryers have been known to be unequal, turn the dryer off and see if it all goes to zero.
The goal is to narrow the unexplained draw to a single circuit, then tear into the circuit to find exactly where the draw is. You can follow the circuit down the chain of receptacles and put the clamp ammeter on the hot wire in each receptacle until you find the leakage.
Be prepared for the possibility that it isn't any sort of theft, but something left on (heater in vacant apartment?) or just appliances that take a lot more power than you thought (air conditioning).