My house was built in 1975 and I pretty obviously have a "Rule of 6" GE main panel (the meter is above this)
My father-in-law (who has taught me a great many DIY things) swears that the neutral bus here is done wrong. (I didn't dare open the top where the meter is, but the bus extends above so I presume the service neutral connects up there.) I won't say he's outright wrong, but with this being the main panel, it looks acceptable to me (inasmuch as a panel of this age can be). I suspect the thick bare ground goes to a rod inside the slab, but I can't open the wall either to check, and I have no ground rods outside the box.
Is this passable, or is the only acceptable way to bond through a binding screw?
Best Answer
It's bonded, alright
Meter-main boxes like yours have their neutral bars permanently bonded to the case at the factory, and thus have a notation on their label saying that they are "suitable only for use as service equipment" (emphasis mine). In your case, this is done through the mounting of the left-hand bar; if you look closely at it, you'll notice that there is no insulator between it and the case, unlike the neutral bars on a typical loadcenter, which are mounted on insulators (whether they be part of the backpan the busbars are attached to, or separate standoffs).