200 Amp Ranch Service Grounding With Multiple Sub panels

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Tjend

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GC & Electrical Project Management
This is a ranch property setup, all separate buildings. Standard 3 bed 2.5 bath house with electric appliances and propane range. Occasional welder use off of a sub panel. Future garage sub panel will be big enough for electric car charger if needed in future. 200 amp service should be plenty for the property. All original wiring/panels (SP-1 & SP-2) from early 2000's unknown installer, not to current code with grounding and wire size. I want these electrical additions done per code even though it is outside any jurisdictions.

See pictures below for more info.

Questions:
Q1 - Confirming all panels after new (MP-1) are to be considered sub panels and will need 4 wires to each sub panel (2 hot, 1 neutral, 1 ground) along with ground bars added and sub panels unbonded.

Q2 - What size ground would you use for the sub panels, 2 AWG AL min or just go with 2/0 AL?

Q3 - Do I connect existing SP-1 T-pole ground rod and SP-2 ufer ground rod to ground bars I am adding in these sub panels, and then the ground bars will also be connected to 4th wire 2 AWG ground going back to MP-1?

Q4 - From new (MP-1) 200 amp main panel to (SP-1) 200 amp sub panel on existing pole and 200 amp house sub panel (SP-2) I intend on using QTY (3) 250 MCM AL and QTY (1) 2 AWG AL ground for the wiring. 4/0 AL is undersized for 200 amps @75 degree C ampacity on the equipment. Wanting to confirm wire order in picture before ordering.

https://imgur.com/1XT1pzU
https://imgur.com/CX5J5Pv
https://imgur.com/sEKjHgO
 
I am headed to bed and dont have time to fully digest, but a few quick things to get you started:

1. It was compliant prior to the 2008 code to have three wire feeders with N-G bonded to detached structures.
2. All available qualifying electrodes at a structure shall be used, and if none exist one must be added. these connect to the service if the structure is fed by a service, or the EGC bus if the structure is fed by a feeder.
3. 4/0 AL is fine on a 200A OCPD per 240.4(B). I do it all the time, even in commercial.
4. EGC's are sized per 250.122
 
Big issue with that outside panel. Romex in conduit underground. Romex is not listed for use in wet areas 334.12(B)(4) Conduits below grade is a wet area per the code 305.5(B).

Missing locknut on conduit entry in outside panel.

Does the main lug only panel that is presumed "inside" have a seperate overcurrent protection (Main breaker) in the visinity of the main lug panel?
 
electrofelon said:
I am headed to bed and dont have time to fully digest, but a few quick things to get you started:

1. It was compliant prior to the 2008 code to have three wire feeders with N-G bonded to detached structures.
2. All available qualifying electrodes at a structure shall be used, and if none exist one must be added. these connect to the service if the structure is fed by a service, or the EGC bus if the structure is fed by a feeder.
3. 4/0 AL is fine on a 200A OCPD per 240.4(B). I do it all the time, even in commercial.
4. EGC's are sized per 250.122
Click to expand...
1. Got it, makes sense on original install
2. EGC buses will be added to SP-1 and SP-2 and connected back to new main service panel MP-1. EGC buses and each building's GEC will all be tied together back to the main service panel and landed on the neutral bus.
3. 4/0 AL will be used. Per 240.4(B) the 2/0 copper feeding SP-2(indoor house 200amp panel) is also ok to reuse when I repull it with a EGC.
4. per 250.122 and 200 amp service - 4AWG is adequate for EGC.
 
Fred B said:
Big issue with that outside panel. Romex in conduit underground. Romex is not listed for use in wet areas 334.12(B)(4) Conduits below grade is a wet area per the code 305.5(B).

Missing locknut on conduit entry in outside panel.

Does the main lug only panel that is presumed "inside" have a seperate overcurrent protection (Main breaker) in the visinity of the main lug panel?
Click to expand...
Most the Romex circuits will be removed, subpanels are being added and eliminating multiple circuits taking up breaker space. There are a couple of UF-B romex circuits in underground conduit running to barns. Are these acceptable to leave, or repull with THHN/THWN.

All missing locknuts and bushings will be added.

MLO indoor panel only has OCPD at the current 200amp breaker in the outdoor panel in the picture (SP-1). Should the indoor panel be replaced with a main breaker panel inside? It would also eliminate the need for another subpanel inside, so not opposed.
 
Around here on the farms or any place served by most rural POCO's the box on pole with meter is not considered the service disconnect regardless what it contains. Sometimes they are fused disconnect, sometimes they are just non fused switch, sometimes a breaker. When loads change and it gets upgraded you may start with something with overcurrent protection and end up with something that doesn't have overcurrent protection. It is almost always the utility that installs that box or ends up replacing if needed. So everything that leaves that pole is generally treated as service conductors and you often find "service conductors" supplying multiple buildings from that pole. If you feed from one structure to another however they expect the separate grounded and grounding conductors for new feeders per NEC.

So I suggest maybe finding out if any such rules or methods of looking at this apply or do not apply in your jurisdiction where this is.
 
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