These guys keep talking about circuit breakers and off-line as if any of that protects against EMP. We'll get some warning on a Carrington Event, but I'd be surprised if they shut down the national grid in advance. And even if they did, yes, Mr. B., there would still be massive damage to the transformer net:
Severe Space Weather--Social and Economic Impacts - NASA Science
Bill, if you have a transformer off-line or the circuit breaker has been properly tripped (fast enough) then a transformer simply won't work, as the circuit isn't complete. IF you have a circuit breaker with a fast enough clamping speed, you MIGHT have a transformer survive, this also assume the circuit breaker is faster than the induced eddy currents. The really big caveat is the the sheer cost of a circuit breaker with a fast enough clamping speed, they are possible, but the necessary alloys are expensive as heck. And they are almost an art-form to make.
The key is that induced currents, inside the transformers, still take a finite amount of time to build up. (It's very, very important at this point, of wether the EMP is acting as a particle or a wave)
Lots of even congresscritters, are fully cognizant of the need of such units, but lots more just flat out don't want pay for such units, just on the chance they might needed.
That's why the necessary warning from NOAA is as critical as the willingness to do the right thing, to act properly, on such warning. Our Western Technic Civilization has the material technology, to give us a really good chance at surviving even a Major CME/Carrington Event, intact, but this assumes our fearless leaders pay for the technology to be in place, or set up the right response to such an event, and thus far things really aren't looking that good. With an EMP bomb, you just flat out not have the time to have the grid prepared properly, but due to massive nature of a CME, you COULD set up the proper response ahead of time. (But then you would have to pay the political cost, if it wasn't needed)