Is it a defect if the grounding conductors are on a separate bus bar from the neutral conductors in the panel that’s the first point of disconnect on the property? I though this was the main panel, but the grounds and the neutrals are separated. Upstream of this panel is the exterior disconnect on a pedestal. Downstream of this is a sub panel.
Main Panel
Sub panel
This means that; electrically speaking, grounding conductors are on a separate bus bar, can be considered a single bus bar. Which means, both grounded (neutral), and equipment grounding conductors can be terminated on either bus bar, from what I understand.
Looks like the bonding screw is still in place.
Looks like there’s a solid bar near the top connecting the two together.
Do you have pics of the “pedestal” with the disconnect? Is this where the meter is located ? That would normally be the service main/disconnect.
I agree. That is typically where the service disconnect is installed.
When was this installed? Prior to the 2008 NEC a 3-wire feeder was permitted to feed a panel at a separate structure. The panel is last photo is on the same structure so the feeder is required to be 4-conductors and the neutral is not permitted to be bonded to the cabinet.
Now that I’m looking at it again, there does appear to be a solid bar/bonding strap that’s running behind the lugs at the top of the main bus bar. Thank you for pointing that out, Timothy.
pedestal with exterior service disconnect. I do not consider it to be a main panel based on the feedback from the local state electrical inspector.
I don’t know when this main panel was installed, as there were no dates on it. The main panel in the first garage is on the attached garage. The sub panel in the third and fourth photos are on the residential structure.
I the bonding screw bonding the strap from the grounding bus bar to the neutral bus bar?
Like Robert said, everything after that meter disconnect should have 4 wire feeds, and those both only have 3 going out. Which would also require those other panels at the home to have the neutrals and grounds separate. But if there is no 4th conductor, or metal conduit, then there wouldnt be anyway to separate. When was the home built?
The home was built in 1903.
So, if they are separated on the other panels, then it actually is a defect in this situation… See what @rmeier2 says as well. But if they are separated, there is no way for the grounding conductors to send overcurrent back to the main disconnect if separated. UNLESS there is metal raceways connecting the panels to each other.
And with no grounding or bonding back to the main panel, then the main service disconnect will not work. Could actually be dangerous, because the grounding would dead end at the home panel.
Robert can correct me if I am wrong… 
Personally, I would just make a comment that the home panels only have 3 feeders, and they need a 4th to properly ground, unless you know there is metal conduit connecting the two.
Make a couple comments about the dangers, and refer to sparky…
Also, do the home panels also have their own ground rod? That would also be required
OK more information so let’s see if we can clear this up:
At the meter these are the Service disconnects in photo below?
Service disconnect on right above feeds this panel below?
Panel above with two 2" conduits in bottom feeds this panel below?
What does the other service disconnect on the left feed? It seems to have much smaller conductors than what is seen in the two panels.
Yes, at the meter those are the disconnects, with the one on the right feeding the main service panel at the home that I inspected.
The exterior service disconnect on the left in the pedestal feeds a separate residential dwelling that I did not inspect.
Yes, the main panel with two 2" conduits in bottom feeds the sub panel in the pictures below.
In the main panel I think that the grounding and neutral conductors were bonded together via a strap behind the lugs of the service entrance conductors, but I’m not totally sure.
I think I understood you correctly, but if there is another “disconnect” inside of a panel, somewhere before entering this panel, yet after the service meter then technically this is a sub-panel and not a main panel even if it services the house as a main panel.
OK, so you have the service disconnect at the meter, (there should have been a grounding electrode connected at the service disconnect).
Up until the 2008 NEC you were permitted to bring a 3-wire feeder to a panel in/on a separate structure and bond the neutral. So the first panel, (the one with the two 2" conduits) is probably OK. There is also a visible GEC and main bonding jumper (MBJ) which is the green screw which is correct.
The second panel if in or on the same structure as the first panel would require a 4-wire feeder. That one appears to have only a 3-wire feeder and the neutral is bonded to the cabinet. Are the two panels in/on the same structure?
The main panel is on the detached garage, and the sub panel is on the house.
There appeared to be a grounding conductor going to a grounding rod at the sub panel, and a grounding conductor went through the bottom of the main panel into a conduit by itself at the main panel. It was unclear if a grounding rod was used at the main panel, but there could be one there that’s not visible. I don’t understand the stuff that you were saying about needing a metal conduit connecting the main panel to the sub panel. There was conduit connecting the main panel to the sub panel.
If a subpanel, (or any panel after the first point of disconnect), there should be 4 conductors for proper grounding, and separation of the neutrals/grounds. But that 4th (grounding) conductor can also be in the form of a metal raceway (pre 2008 I believe)
Because the metal raceway, if properly bonded at each end to the panels, acts as the conductor.
Assuming the circuit grounding conductors are also bonded to each panel enclosure.
If the conduit is plastic, then there is no possible way to separate the grounds and neutrals as required with only 3 conductors
The metallic raceway can still serve as the grounding post 2008 Code.