Is it OK to have the main disconnect at a combination enclosure at the meter instead of at the main panel (wired as a main panel)?
absolutely and very common… easier for fire dept access
That would be the service equipment (where the service disconnect is located). The other panel would be load side equipment and should have a four wire feed with isolated neutrals. . .
What I am seeing a lot of is a pedestal type meter/disconnect that feeds, via a lateral, a panel on the outside of the home that may or may not feed a load side panel in the garage. Typically, the panel at the outside of the home is wired as a service equipment panel with the neutrals & Gnd bonded together and 3 wires from the pedestal disconnect. The GEC to the ground rod or other grounding means enters the outside panel and is connected to the Gnd buss there.
There are split neutrals with a tie bar, but the bonding screw was missing at the neutral bus and the grounding bus bar was connected directly to the box. If the disconnect is in a separate panel, as it is, this seems correct to me.
4 wire feed? I see two hot conductors, one insulated neutral conductor and one uninsulated stranded aluminum conductor that looks like a neutral (there was another sub-panel in the garage). If the unisulated aluminum wire is the grounding conductor (GEC) why isn’t it single strand copper?
That’s a proper set-up Kenton. It’s a four wire feed with isolated neutrals. It is not the service equipment.
The service equipment has the service disconnect (pic #1).
Ah-ha! GEC goes from the service equipment (combination meter/disconnect enclosure to a grounding electrode. The stranded aluminum conductor is one of the isolated neutrals.
Thanks, Jeff.
Michael, what you have described is common but improper. The “pedestal” is the service disconnect. The lateral should include a four wire feed to the next panel(s), which be considered “remote” panel(s).
The pedestal should have its own grounding electrode and the building should have one as well.
There may be some sparkies that will disagree because there are some exceptions to this, but as a home inspector, this is what you should expect to see, otherwise it should be deferred to an expert for verification.
Almost Kenton. 
The bare stranded conductor is the equipment grounding conductor (EGC), which should be attached to the grounding bus in the load side panel.
Ooop, yep, you can see it under the lug at the top of the grounding bus bar in picture #2.
lol…Jeff beat me to it…lol…yep thats the EGC…not the GEC…
One careful item with service disconnects separate from the service panel, [other ensuring the unbonding of neutral and ground bars], check where the grounding electrode conductor(s) is attached.
Heard stories where the outside electrician thought the inside electrician was doing ‘them’, and vice-versa. 
tom
lol…outside electrician and inside electrician…lol…man where I come from only (1) electrician on the job…lol…and he is KING…the helpers dont get to mess with the panels…lol…not in my electrical company anyway…lol
But I am ANAL like that…
Hey, doesn’t show. 
I’m saying in new construction. You should see the yahoo’s that do the work, since the house isn’t hooked up yet, no PPE and they move around like misguided army ants.
later,
tom
Tom,
Oh I hear ya brother…many times and in many states the actual guys out wiring the house do not even have to be licensed…they work under the owners license…sad but true…and who knows WHAT they might do…
For example…I caught (2) AHJ’s today signing up for a local seminar I am doing that did not understand grounding and bonding correctly, AFCI’s Correctly and a few other things…so IMAGINE how the local guys who actually DO the work are doing it…scary…