Yesterday I did an inspection in which the electrical service was unusually configured. The service entrance cable ran to a main fuse box, with bonded neutral and grounding lugs, which were connected to the grounding rod and supplemental water pipe grounding electrodes.
This ran about 15 feet to the branch circuit breaker panel with 3 wires: 2 hots (240V service) and a neutral wire. The circuit breaker panel had one neutral bus bar (which did not appear to be bonded to the panel, and to which branch circuit grounds and neutrals were connected) and the branch circuit breakers.
The neutral bus bar was very crowded, with double-tapped neutrals, and little room to work, and only had one large lug for the incoming neutral.
In any case, this does not seem proper, at least by today’s standards. It appeared to have been done by a professional electrician at least 25 years ago.
My thought is that the easiest way to correct this is to install another bus bar in the breaker panel for the grounding wires, and for that bus bar to be grounded and bonded as a main panel would be.
I don’t have photos here because they’re on my laptop, which I rarely use for the internet. May add them to the post later.