As Noel has indicated, he would like the breakers on the M-7...
Penn Central,
As an [LIRR] Electrician, I like the breaker setup on the M-7 also.
Some thought finally went into setting up the electrical distribution system.
As you know, the breaker numbering even makes sense. Any breaker number from 1 up to 100 is low voltage; in the 100's is 120 volts; 200's is 220 volts, etc.
Even better for us Electricians, all the low voltage breakers are two pole breakers... the breaker, when shut off or tripped, breaks the positive
and negative feeds to the circuit, making [the inevitable grounds as the cars get older] grounds easier to isolate.
Contrast that to the M-1, where the low voltage negative buss is one big morass, and a pain to isolate grounds. They improved a little on that with the M-3, but certain grounds still read across several major circuits.
One major negative thing about the type of breaker used in the M-7 is that they cannot differentiate between a breaker being tripped or shut off.
When a security lighting breaker is shut off, for example, the Engineer keeps getting a trouble screen ["breaker is tripped"] flashing and beeping throughout his trip. And he/she doesn't like it.
As far as the high voltage breakers not being accesible to the crew...that is probably just the natural migration away from having high voltage equipment in the cab.
We've gotten to the point where there is no 750 in the cab at all in the M-7 AFAIK. Even cab heat is no longer rail voltage.
As an aside, many people don't know this, but the load meter in the M-3 [and I would presume the M-3a...my blueprints say "LIRR and H/H"...perhaps Dutch can recall from his M of E days if this is true on MNR M-3a] is not directly in the 750 volt circuit, even though the shops keep labeling the M-3 load meter "Danger 750 volts" (on the LIRR, anyway), because at least a few of them have gone "poof" over the years in the M-1. The M-3 load meter is driven by an electronic card that monitors the traction motor current. The only 750 in the M-3 cab is in the cab heat enclosure.
Tom