Site-Isolating Device. Site-isolating devices shall comply with 547.9(A)(1) through (A)(10).

(1) Where Required. A site-isolating device shall be in- stalled at the distribution point where two or more agricultural buildings or structures are supplied from the distribution point.

(2) Location. The site-isolating device shall be pole- mounted and shall meet the clearance requirements of

230.24.

(3) Operation. The site-isolating device shall simulta- neously disconnect all ungrounded service conductors from the premises wiring.

(4) Bonding Provisions. The site-isolating device enclo- sure shall be connected to the grounded circuit conductor and the grounding electrode system.

(5) Grounding. At the site-isolating device, the system grounded conductor shall be connected to a grounding electrode system via a grounding electrode conductor.

(6) Rating. The site-isolating device shall be rated for the calculated load as determined by Part V of Article

220.

(7) Overcurrent Protection. The site-isolating device shall not be required to provide overcurrent protection.

(8) Accessibility. Where the site-isolating device is not readily accessible, it shall be capable of being remotely operated by an operating handle installed at a readily accessible location. The operating handle of the site- isolating device, when in its highest position, shall not be more than 2.0 m (6 ft 7 in.) abovegrade or a working platform.

(9) Series Devices. An additional site-isolating device for the premises wiring system shall not be required where a site-isolating device meeting all applicable requirements of this section is provided by the serving utility as part of their service requirements.

(10) Marking. A site-isolating device shall be permanently marked to identify it as a site-isolating device. This mark ing shall be located on the operating handle or immediately

adjacent thereto.

(B) Service Disconnecting Means and Overcurrent Pro- tection at the Building(s) or Structure(s). Where the service disconnecting means and overcurrent protection are located at the building(s) or structure(s), the requirements of 547.9(B)(1) through (B)(3) shall apply.

(1) Conductor Sizing. The supply conductors shall be

sized in accordance with Part V of Article 220.

(2) Conductor Installation. The supply conductors shall be installed in accordance with the requirements of Part II of Article 225.

(3) Grounding and Bonding. For each building or struc- ture, grounding and bonding of the supply conductors shall be in accordance with the requirements of 250.32, and the following conditions shall be met:

(1) The equipment grounding conductor is the same size as the largest supply conductor if of the same material, or is adjusted in size in accordance with the equivalent size columns of Table 250.122 if of different materials. (2) The equipment grounding conductor is connected to the grounded circuit conductor and the site-isolating device at the distribution point.

(C) Service Disconnecting Means and Overcurrent Pro tection at the Distribution Point. Where the service dis connecting means and overcurrent protection for each set of feeder conductors are located at the distribution point, feeders to building(s) or structure(s) shall meet the requirements of 250.32 and Article 225, Parts I and II.

FPN: Methods to reduce neutral-to-earth voltages in livestock facilities include supplying buildings or structures with 4-wire single-phase services, sizing 3- wire