GROUNDING AND BONDING, LEVEL 2 LESSON 3

A(n) ? is a premises wiring system where power is derived from a source of electric energy or equipment other than a service. Such systems have no direct connection from circuit conductors of one system to circuit conductors of another system, other than those established through bonding or grounding connections. - Answer-separately derived system Which of the following is typically not a separately derived system? - Answer-a. Autotransformer with a grounded conductor common to both the primary and secondary A(n) ? is the connection between the grounded circuit conductor and the supply-side bonding jumper or the equipment grounding conductor, or both, at a separately derived system. - Answer-d. system bonding jumper Where a system bonding jumper for a separately derived system is a wire type, it is required to be sized using Table 250.102(C)(1) or the 12.5% rule based on the size of the largest derived ungrounded phase conductor(s) or the total circular mil (cm) area of all conductors connected to any one ungrounded phase at the source. - Answer-True Which of the following locations is permitted for installing the system bonding jumper for a separately derived system (transformer type)? a. A connection between the first disconnecting means enclosure and the source enclosure b. The first system disconnecting means enclosure c. The second overcurrent device enclosure (subpanel) supplied by the system d. The service equipment enclosure e. The source enclosure f. Both b. and e. for the same system by exception - Answer-b., e., and f. If a separately derived system has 600 kcmil copper secondary ungrounded phase conductors, what is the minimum size required for a copper, wire-type system bonding jumper? - Answer-c. 1/0 AWG The ? is a conductor installed on the supply side of a service or within a service equipment enclosure(s), or for a separately derived system that ensures the required electrical conductivity between metal parts required to be electrically connected. - Answer-c. supply-side bonding jumper If a generator is installed on a premises wiring system, it must be grounded as a separately derived system if there is a switching action in the grounded conductor through the transfer switch. - Answer-True The grounding electrode conductor for a single separately derived system shall be sized in accordance with ? . - Answer-NEC TABLE 250.66