136 lines
3.3 KiB
Markdown
136 lines
3.3 KiB
Markdown
---
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id:
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aliases:
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- feeders takeoff
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title: Feeders Takeoff
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tags:
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- occupational/takeoff
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- status/draft
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- type/guide
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up: "[[takeoff-scripts]]"
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---
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# Feeders Takeoff
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> [!important]
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> Complete [[pre-takeoff-research]],
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> including [[conest-wiring-method-selection]],
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> before beginning takeoff.
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## Scope
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* Primaries
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* Secondaries
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* Feeders
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* Grounding
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### Formatting
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All feeder takeoff descriptions should be prefixed with `<parent> TO <child>`
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It is acceptable to use typicals for identical feeders
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(i.e. meter centers fed from bus plugs)
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so long as the typical is in `Area` = "01 - Feeders/Risers ...".[^1]
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[^1]: [[2025-08-15_14-15-41]]
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### Routing
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Run parallel to building lines
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and route through corridors where possible.
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> [!important]
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> All takeoffs in Systems with names including "site"
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> should be in "Site" Area, Phase, and Bid Item breakdowns.
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For adjacent panels, use a minimum 10ft length.
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#### Adders
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Use the difference in elevation between equipment[^2]
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or 10ft, whichever is greater.
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[^2]: Not actually difference in elevation.
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A site run from the bottom to the top of a hill may still only need 10ft.
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This needs more precise wording.
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It is not necessary to change this logic for site runs.[^3][^4]
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[^3]: [[2026-06-03_14-05-39#Site Run Adders]]
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[^4]: I will remove this line when I break the habit.
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## Primaries
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> [!info] Breakdowns
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> * `Area` = "2 - Site"
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> * `Phase` = "Site"
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> * `System` = "PRI - Primaries"
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Usually only empty conduit if included.
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## Secondaries
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> [!info] Breakdowns
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> * `Area` = "2 - Site"
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> * `Phase` = "Site"
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> * `System` = "SEC - Secondaries"
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### Wiring on Vault Racks
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Where secondary conductors run on racks in utility vaults
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manually set the length of conduit,
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measure the wire length,
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add 20ft in addition to previously mentioned adders.[^5]
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[^5]: [[art-baldwin]] at some point, I think.
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## Feeders
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> [!info] Breakdowns
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> * `Area` = "01 - Feeders/Risers Building"
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> * `Phase` = "Feeders"
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> * `System` = "FRR - Feeders and Risers"
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> [!info] Garage Feeders
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> `Area` "01 - Feeders/Risers Garage" is seldom used.
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> It may be appropriate for totally separate parking garage buildings.
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> Seek clarification before using.
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## Bus Duct
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`COMMON ASSEMBLIES`/`DISTRIBUTION`/`BUS DUCT`/...
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Delete unnecessary items and change `Fct 1`
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to get the correct quantities for the use case.
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## Conductor Support
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In lieu of more stringent requirements
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that may be imposed by project requirements,
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minimum support for vertical conductors
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is determined by [[nfpa-70_300_general-requirements#300.19(A) Spacing Intervals --- Maximum.|NEC 300.19(A)]]
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Various [[heuristics]] exist among ConEst teams.
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Assuming minimum 40ft spacing
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(the absolute minimum for feeders we're likely to encounter)
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for _all_ conductors is popular even among more detail-favoring seniors.
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I generally prefer not to use a heuristic
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because `takeoff-calcs.xlsm` trivializes accurate selection
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and results in far fewer necessary supports.
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Like [[#Sleeving]], it is acceptable to takeoff total counts
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`ITEM DATABASE`/`CONDUIT & FITTINGS`/`CABLE SUPPORT / WEDGES`/`... COMPLETE FITTING`/...
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## Grounding
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See [[grounding-takeoff]].
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## Sleeving
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See [[sleeving-takeoff]].
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Because feeders are not broken down by level
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(they use `Area` = "01 - Feeders/Risers ...")
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it is acceptable to use total counts.
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