John Beckman wrote:
Greetings,
I was looking at a 1955 bungalow with what is probably an updated electrical
panel. However, there was no typical "main breaker" at the top, there were
just two rows of breakers on each side. the stove and water heater had the
typical tied breakers that would indicate that it is a 240 volt breaker.
However, at the top left side of the panel there were three 100 amp
breakers, side by side with their handles tied together. If it was just two
tied together, I'd just say OK 100 amp service and these are the mains, BUT
there were three of them. What gives, I'm thinking of buying the place and
want to know what kind of elec service it has. Unfortunately I did not
remove the panel cover, and I don't know the brand. Suggestions? Speculation

From your description I infer that you're dealing with 120/208 volt
3-phase service with a 100 amp main.