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400 Amp Service

400 Amp Service

400 Amp Service

(OP)
The local utility company supplies a Ronk 400Amp meter base with a disconnecting means. I want to run parallel 4/0-4/0-2/0 alum to two 200 amp disconnects. The Ronk meterbase says it is listed for a service disconnect, but has no OCPD.
Is this considered my first disconnecting means? Do I have to bond neutrals and ground at this point? Do I carry a 4th wire for equipment ground to 200Amp panels with OCPD and isolate neutrals and grounds like a subpanel feed Art. 250.32(B)1.  

RE: 400 Amp Service

Per NEC 230-91, "the service overcurrent device shall be integral to the service disconnecting means or shall be located immediately adjacent thereto."

NEC 230-90: "Two to six circuit breakers or sets of fuses shall be permitted as the overcurrent device to provide overload protection. The sum of the ratings of the circuit breakers or fuses shall be permitted to exceed the ampacity of the service conductors provided the calculated load in accordance with Article 220 does not exceed the ampacity of the service conductors."

You must bond the neutral to ground at the service disconnect, which in this case would be the meter. Downstream of the meter, the neutral must not be grounded (unless multiple buildings are involved). You don't need to run the neutral past the meter if you don't need it for the loads.

RE: 400 Amp Service

Meter disconnect switches are permitted ahead of the service disconnect per NEC-2002 230.82(2).  The meter disconnect is not the service disconnecting means (see comments after 230.82(2) in NEC-2002 Handbook).

RE: 400 Amp Service

Suggestions to mashen96 (Specifier/Regul) Feb 24, 2004 marked ///\\\
The local utility company supplies a Ronk 400Amp meter base with a disconnecting means.
///The Utility normally has a book of various requirements and practices that are expected to be followed by the Electrical Contractors.\\\
I want to run parallel 4/0-4/0-2/0 alum to two 200 amp disconnects.
///Check if the 4/0 is large enough for a 200A disconnect in terms of the Utility requirements.\\\

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