I am confused about a couple of items from Mike Holt's NEC Exam Preparation Guide.
The practice questions in Unit 10 have four questions concerning Bonding Jumpers and Grounding Electrode Conductors.
Questions 24 and 35 relate to Bonding Jumpers.
Questions 25 and 36 relate to Grounding Electrode Conductors.
Questions 24 and 35 seem to use 400 kcmil & 500 kcmil conductors respectively to find the Bonding Jumper size in Table 250.66.
400/500 kcmil being the conductor size in a single raceway.
Questions 25 and 36 seem to use 400 kcmil x 3 (1200) & 500 kcmil x 2 (1000) conductors respectively to find the Grounding Electrode Conductor size in Table 250.66.
1200/1000 kcmil being the sum of the conductors from all raceways.
In Unit 12, the Bonding Jumper and Grounding Electrode Conductor examples on pages 356 & 357, show multiplying the size of the non-grounded conductors by the number of raceways for sizing in both situations.
This appears to be a contradiction to the test questions in Unit 10.
I apologize for the long narration, but this has confused me for quite some time.
Can anyone help me resolve this apparent discrepancy or show me where I have gone astray?
The practice questions in Unit 10 have four questions concerning Bonding Jumpers and Grounding Electrode Conductors.
Questions 24 and 35 relate to Bonding Jumpers.
Questions 25 and 36 relate to Grounding Electrode Conductors.
Questions 24 and 35 seem to use 400 kcmil & 500 kcmil conductors respectively to find the Bonding Jumper size in Table 250.66.
400/500 kcmil being the conductor size in a single raceway.
Questions 25 and 36 seem to use 400 kcmil x 3 (1200) & 500 kcmil x 2 (1000) conductors respectively to find the Grounding Electrode Conductor size in Table 250.66.
1200/1000 kcmil being the sum of the conductors from all raceways.
In Unit 12, the Bonding Jumper and Grounding Electrode Conductor examples on pages 356 & 357, show multiplying the size of the non-grounded conductors by the number of raceways for sizing in both situations.
This appears to be a contradiction to the test questions in Unit 10.
I apologize for the long narration, but this has confused me for quite some time.
Can anyone help me resolve this apparent discrepancy or show me where I have gone astray?