I am building a house in a 3rd world country and have run into a dilemma. We are installing a 200Amp meter and were initially planning to run one 4/0 aluminum cable to the main panel in the house.
Since then we have decided to build a shed, which has its own (smaller) panel that will feed the reserve water tank pump, pool pump, washer/dryer, some exterior lights, the gate and probably more things later.
The electrician was planning to run a 1/0 cable from the house panel to the sub-panel in the bodega. I would prefer to A) not take up any more spaces in the main panel, B) be able to run a decent size load on the shed panel. So I asked him to run another 4/0 aluminum cable (because it appears that's what's required for a 200Amp load) straight from the meter to the panel in the shed. He's saying that connecting 2 4/0 cables inside the meter is impossible because of the terminal size limitation. He's suggesting we run a 2/0 cable for the shed, as anything larger will not fit in the terminal alongside the 4/0 cable.
My question is: assuming the load on the shed panel never exceeds 50Amps as he says (let's say 100 to be on the safe side), is it safe to run an additional 2/0 aluminum cable on the same lug on the 200Amp meter? If it is safe to do that, would it be safe to run a 1/0 or thinner cable, as long as it is rated for the load the shed panel will need? Are there double lugs that would accommodate a 4/0 and a 2/0 (or smaller) cables? Would combining the 4/0 cable with the 2/0 cable under one lug be OK? If not with a 2/0 cable, with what size?
Some other information:
In this country a double terminal for the meter is not possible to purchase, and I wouldn't even know what to order on Amazon from the US. But if I could get one, and it allows us to connect 2 4/0 cables at the meter, would this be fine?
Copper is prohibitively expensive here, so running a 2/0 copper cable instead of a 4/0 aluminum cable is pretty much out of the question. Plus we already have the 4/0 cable to run to the house.
All of this is discussed in Spanish, and I'm translating this into English. And I'm not super savvy when it comes to this stuff. So I'm sorry if there are terminology mistakes in this question.
Best Answer
The solution is (essentially) a small but heavy-duty panel at the meter. These are often designed as a combination (look for "meter main") so that you can feed a handful of large loads and/or subpanels from the meter - which is exactly what you are trying to do. Avoids double-tapping the lugs and provides a safe shutoff for each subpanel separately so that you only need to get the power company involved one time, unless you need to replace the meter main.
Something like this Eaton CH 200A 8-space:
They have some slightly smaller ones, but I wouldn't go smaller than 8 spaces, because each 240V circuit will take 2 spaces. So from a practical standpoint, I would consider it as a panel to feed up to 4 subpanels. But, for example, you might have 2 subpanels (as planned) and use one of the spaces for a convenience circuit or for outdoor lighting.