POWER: San Mateo/San Francisco power outage report


just a minor note ont he initial cause. They grounded the system just fine,
then just forgot to pull the safety grounds before they repowered the line.

As for "power grid outages shouldn't spread", there's a rule in that biz, it's
always easier/faster to reset 10 circuits that replace something. If you leave
a turbine generator up in a situation where output load is whacked, you could
be looking at a several week outage. The reason it took them so long to get
the plants back on line is they have to do a complete system inspection to
make sure the breakers tripped in time.

One other thing to remember, there isn't a whole lot of risk working on a
router outage. When you're restoring electric service, you have to go slower
so you keep the possibility of frying a lineman to a minimum. I spent a few
weeks installing power line electronic equipment in a 115kv substation and got
a whole new level of respect. You couldn't pay me enough to do that work (but
I like their trucks.)


Yeah, your first mistake around that kind of energy is almost always your last.

I used to a lot of work with embedded control systems in very-high-power
microwave transmitter gear (ie: 25KW stuff). Those things run around
with several tens of KV at ~2A (yes, that's AMPS) in the HV drawer. Even
"pedestrian" HPA hardware (3kw Cband stuff) has a couple hundred ma in the
HV drawer, which at 20kv is more than enough to fry you very dead.

If you manage to route that kind of energy through yourself (and it WILL jump
air gaps at that voltage) they don't even bother with paramedics - just call
the coroner. That ignores the risk from the emitted microwave energy
itself, which is substantial as well (directly in the front of the antenna
the ERP of these things can be in the range of a couple of MW - more than
enough to cause you all kinds of physiological trouble (like death))

And that's NOTHING compared to the energy levels running around in circuits
at 115kv substations!