New Service to existing home, Plus new buildings

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aort11

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Right now I have a 200 amp service in a home. It goes from the transformer to meter via 3 wire 4/0. The meter is at the house, then to the main 200 amp disconnect in the panel. The goal is to do the following:

Ronk Model 7406MS (Meter base and transfer switch all in one)
2 x Siemens W0202MB1200CU (200 amp disconnect)

All 3 boxes mounted on a pole with the service coming from the pole to the meter. This is where I start to get confused. I know you are supposed to bond the N and G at your first disconnect, but would that be the transfer switch? It is not fused. I only have a 3 wire run to the home, so if I bond at the meter/xfer switch I'll need to add a ground to the home. The switch will also be feeding the 2 200 amp disconnects for detached buildings. The disconnects are there for Generator operation. There will be cable/communication lines from the buildings to the home. I know the two 200 amp disconnects should have the neutral and ground bonded with 4 wire feeding the buildings. My thought was to leave the home feed with 3 wire, unbonded N and G in the meter/xfer switch, Bonded at the main panel in home, then bond the N and G in each of the 200 amp disconnects before they feed the two other buildings with 4 wire.
 
To me the problem is deeper.
I'm having the same problem jxofaltrds noted above.
The website for that switch states:
NON-UL & NOT-SUSE RATED
As I see it, the requirement of 230.91 for the OCP to be integral with or immediately adjacent to the disconnect means precludes this switch being used as a service disconnect and 230.82 would not allow it ahead of your service disconnect.
I certainly may be mistaken, but to me the answer would be to supply a SUSE switch which would have OCP and thus make all downstream disconnects sub-panels.
 
Though not the Ronk brand we have utility companies in rural areas providing an equivalent type of disconnecting/transfer equipment in a lot of instances. - I have one myself where I live. They have a pole mounted box that contains metering equipment, followed by a double throw switch - no overcurrent devices at all. They usually have anywhere from four to six possible load termination points (and often conductors doubled up - but that is a different issue).This unit is not listed - and therefore POCO's are the primary places that can get by with providing them, most contractors are bound by NEC and if it isn't listed it isn't going to pass inspections where required.

We always treat anything that leaves these enclosures as service conductors - they do not have any overcurrent protection on them. POCO can install these for less cost (customer does pay for them, they used to be no charge if you had all electric heating or other high load conditions that may shorten payback if they don't charge for them) then a contractor can install proper listed transfer equipment for. In fact I even cost myself some sales by recommending to customers to have the POCO install said equipment instead of me selling/installing them some transfer equipment.
 
I've been around some of these meter/transfer switches which are supplied by the utility companies but seems a little sticky to say that they are a POCO piece of equipment when they are giving you these to be able to connect a homeowners generator to them.
As far as the grounding, I would do it at the transfer switch and then run new 4wire to house and separate neutrals/grounds.
 
mopowr steve said:
I've been around some of these meter/transfer switches which are supplied by the utility companies but seems a little sticky to say that they are a POCO piece of equipment when they are giving you these to be able to connect a homeowners generator to them.
As far as the grounding, I would do it at the transfer switch and then run new 4wire to house and separate neutrals/grounds.
Click to expand...

They have the meter section sealed to prevent meter tampering, the double throw switch is customer accessible, not only can the customer connect a generator but additional loads are pretty easy to connect as well. This is common with rural POCO's around here. On the farms you have a "distribution pole" and multiple buildings all come from this pole. Modern farming methods are requiring bigger services, three phase services, even 480 volt three phase services. Maybe the need for such a central distribution pole is not as great as it once was, but that practice is still there, and even the NEC mentions such site isolation in art 547 though 547 is really more about livestock buildings then about the entire site.
 
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