That can't be a 3Ø meter.
Unless you guys do things very differently in the US with 3Ø supplies, wouldn't there need to be more wires on the LOAD side of the meter?
Well, there is corner grounded delta, but that was never done in houses.
My grandmother's house, built in the 1890's, had a 120V 15A service, and fuses in the neutral, as well in the hot wires. Back in the early days, there was some concern that neutrals might get overloaded somehow. The house had the earliest form of BX cable, but no knob and tube.
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measure once, cut once, then redefine the requirement...