UL 98:2004 pdf download – Enclosed and Dead-Front Switches.
6.11 DisconnectIng means of the grounded service conductor
6.11.1 An enclosed switch shall be provided with a means for disconnecting the grounded service conductor from the load conductors piovided that it is acceptable for use as service equipment and that it has provisions for the connection of a grounded service conductor.
6.11.2 The required disconnecting means may be:
a) A link, screw, or similar conducting piece intended to make connection between two terminals,
b) A terminal plate provided with wire connectors or lugs or with wire binding screws and upturned tugs for damping a 10 AWG (5.3 mm2) or smaller wire,
C) A single stud provided with wire connectors or lugs. or with nuts and cupped washers for clamping a 10 AWG (5.3 mm2) or smaller wire,
d) A wire connector that Is intended for the connection of a single conductor and also for the connection of two conductors, or
e) A single wire connector between the grounded load conductor and the grounded service conductor, as well as the connection of the grounding electrode conductor, provided the grounded load conductor can be removed without disturbing any other conductors.
6.11.3 Where the disconnecting means is a removable link or a switching neutral pole, the provisions for connection of the grounding electrode conductor and the main bonding jumper shall be on the line side of the disconnect link or switching neutral pole.
6.12 Provision for grounding
Note: The grounding and bonding terms used in this section are in accordance with the UL column in Appendix 0. The corresponding CEC and ANCE terms are also provided for information.
6.12.1 An enclosed switch acceptable for use as service equipment shall have provision for connection of the grounding electrode conductor to the grounded service conductor terminal. The size of the grounding electrode conductor shall be In accordance with Table 12. A soldering lug or other connection means that depends upon solder shall not be used.
6.12.4 In Mexico and the United States. the following applies. It there is no provision for the load conductor mentioned in 6.12.3. the grounded service conductor wire connector shall:
a) Accommodate a conductor of the same size as the main bonding jumper specified in Table
12,
b) Be bonded to the enclosure, and
C) Be directly connected to the grounding electrode conductor wire connector.
6.13 ProvIsion for bondIng
Note: The grounding and bonding terms used in this section are in accordance with the UL column in
Appendix 0. The corresponding CEC and ANCE terms are also provided for information.
6,13.1 The bond between the installed equipment grounding conductor and the conductive parts of the
frame or enclosure shall comply with the requirements of 6.132 — 6.13.8.
6.13.2 When an insulated neutral is provided for an enclosed switch that is acceptable for use as service equipment, a main bonding jumpef shall be provided to bond the enclosure to the insulated grounded circuit conductor (the insulated neutral) of an ac circuit.
6.13.3 The bonding jumper shall have a cross- sectional area as indicated in Table 12.
6.13.4 If an insulated neutral is provided, the construction shall be such that when the bonding means is not used, the spacings given in Table 2 will be obtained.
6.13.5 Unless the intended use and method of installation of the bonding means are obvious, such means shall be accompanied by instructions for installing.
6,13.6 If the main bonding jumper is a screw, the screw shall have a green-colored head. The screw shall be visible without disassembly or removal of devices inside the enclosed switch.
6.13.7 Screws located in the backs of enclosures and used to secure grounding conductors of nonmetallic sheathed cables shall not project past the back of the enclosure by more than 1.6 mm (0.063 inch) when a 16 AWG conductor is In place under the head of the screw. With the maximum intended size of wire in place, the screw shall engage at least two lull threads.