Electrical – Is this a split bus electrical panel

I got an answer from my electrician. Here are the options in order of preference with pros and cons

1. Replace the panel - Pro: all new box and breakers; Con: Somewhat expensive
2. Replace with "cheaters" to make space - Pro: Cheaper; Con: Still expensive (labor) and the wires may not be long enough to reach where they need to reach.
3. Replace the 220v A/C disconnect with a fusible disconnect - Pro: Cheap; Con: Not entirely to code, have to replace fuses, in my case the outside box would have to be replaced too.

I went with replacing the panel. It cost $1600 and took about 6 hours. Expensive but its the right solution and I have a few free breakers to add some circuits if I ever need them. The old box had a few other tabs that looked fishy, it was a good idea to let it go.

If this is the only panel box, or the main panel box, then the neutral and ground wires may terminate at the same set of bus bars. This is where the neutral and ground wires are bonded together. What we might be seeing is a dual bus bar setup that is stacked and offset like stadium seating. They are likely permanently bonded together. There is no stipulation in the order of termination so long as only one wire is secured per terminal (unless the manufacturer specifies otherwise).

The ground wires outside of the box are improperly terminated. They should run into the box and to those bus bars. Look at the corrosion and dirt on that twisted mess. It most likely is not able to conduct fault current properly to trip a breaker. That's a fire and electrocution hazard right there.

Splices in the panel box are allowed so long as they are properly spliced and the total wire volume does not fill the panel to the point where you need to squeeze the cover on or tamp the wires so the cover fits.

Multiple cables through a single clamp is also a violation as the clamps are only rated to secure a single cable. The only way multiple wires can terminate to the same knockout is if the clamp is rated to do so. Standard clamps in the picture are rated for a single cable only. Multiple wires in a single clamp can slide against each other allowing them to pull out. So the dunderhead electrician tightens the clamp even more possibly damaging the cable in the process.

This is an older panel box which was built in a time where the NEC didn't stipulate more room for a panel box. Modern boxes have much more room. Tandem breakers or skinnies are allowed only if the number of circuits does not exceed the panels rating. E.g. a panel rated for 20 circuits which has 20 spaces (a 20/20 panel) can only have 20 circuits regardless of the type of breaker used. You could have 5 tandems and 10 singles for a total of 20 circuits. It can not be filled with 20 tandem breakers for 40 circuits or any combination which exceeds 20 circuits UNLESS the panel has a higher circuit to space rating like 20/40. This change was done in 2014 to alleviate overcrowded panels.