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The older meters had serial-numbered lockout tags that would break if you attempted to remove them, that prevented access to the mechanicals of the meter under

The older meters had serial-numbered lockout tags that would break if you attempted to remove them, that prevented access to the mechanicals of the meter under the glass. I imagine that the gearing in the meter had some mechanism to prevent a simple 'rewind' attack. I also imagine (Hope?) that the power company would measure @ the pole level at some key points to make sure everything added up, and they have lots of data to help spot discrepancies.

brewtide 5y ago
Rumor has it back in the day, a relatively strong, well placed magnet would certainly slow the rotation of the metering dial...
- sethhochberg 5y ago
  ...though once this kind of attack became common, the utility meter manufacturers started adding anti-tamper features like hall effect sensors that record the presence of an unusually strong magnetic field near the meter equipment. You'd get some questions next time the meter reader came around and the tamper indicator was lit. Utilities have a lot of financial incentive to keep people from (at least blatantly) manipulating their billing.
  - thrashh 5y ago
    I wonder if you could screw with someone you don’t like by putting a big fat magnet on their meter. Ofc with the new prevalence of home cameras, that would be risky now.
stordoff 5y ago
>I imagine that the gearing in the meter had some mechanism to prevent a simple 'rewind' attack. Big Clive details one of the attacks on older (UK) meters here: https://www.youtube.com/watch?v=gFtB0C0rBaM https://www.youtube.com/watch?v=gFtB0C0rBaM It was possible to run them backwards. He mentions possible evidence this would leave behind, and notes (taken from the description): > Latterly devices to detect this activity were added to meters in the form of non-resettable flags that would move out if the meter ran in the wrong direction, or in the case of digital meters a tamper indicator.

brewtide 5y ago

Rumor has it back in the day, a relatively strong, well placed magnet would certainly slow the rotation of the metering dial...

sethhochberg 5y ago
...though once this kind of attack became common, the utility meter manufacturers started adding anti-tamper features like hall effect sensors that record the presence of an unusually strong magnetic field near the meter equipment. You'd get some questions next time the meter reader came around and the tamper indicator was lit. Utilities have a lot of financial incentive to keep people from (at least blatantly) manipulating their billing.
- thrashh 5y ago
  I wonder if you could screw with someone you don’t like by putting a big fat magnet on their meter. Ofc with the new prevalence of home cameras, that would be risky now.

stordoff 5y ago

>I imagine that the gearing in the meter had some mechanism to prevent a simple 'rewind' attack. Big Clive details one of the attacks on older (UK) meters here: https://www.youtube.com/watch?v=gFtB0C0rBaM https://www.youtube.com/watch?v=gFtB0C0rBaM It was possible to run them backwards. He mentions possible evidence this would leave behind, and notes (taken from the description): > Latterly devices to detect this activity were added to meters in the form of non-resettable flags that would move out if the meter ran in the wrong direction, or in the case of digital meters a tamper indicator.