Cable Handling

1
Cable Handling
2
Electrical Conduit and Boxes
3
Objectives

• List 4 types of electrical boxes or enclosures
• List 4 types of conduit
• Describe the concept of conduit capacity

4
Electrical Boxes

• Electrical boxes vary in size and function
• Ganged boxes
• NEMA enclosures
• Pull boxes
• Equipment racks

5
Electrical Conduit

• Conduit comes in various configuration
• EMT Electrical Metallic Tubing
• Also called thinwall
• IMC Intermediate Metal Conduit
• RMC Rigid Metal Conduit
• PVC Polyvinylchloride

6
Conduit
7
Electrical Conduit

• Conduit comes in various sizes
• ½, ¾, 1, 1-¼, 1-½, 2, 2-½, 3, 4
• For the same size conduit- EMT, IMC and RMC may
  have a different inside area

8
Electrical Conduit

• Pull boxes are intermediate points within a long
  or complex conduit run
• Pull boxes should be installed
• Any time there is greater than 180 of bends
• Over 100 foot run

9
Electrical Conduit

• Conduit Capacity
• According to the N.E.C., there is a limit to how
  much cable can fit into a conduit.

10
Plenum Spaces
11
Plenum Spaces

• What is a plenum space?
• What we really want to discuss is the proper
  term Return Air Plenum
• A Return Air Plenum is any enclosed area designed
  for circulating airflow within a building
• It is the opposite of a ducted return air system

12
Plenum Spaces

• Why are return air plenums used in construction?
• Cost effective method
• Reduces expensive ductwork
• Saves space in the ceiling

13
Plenum Spaces

• Why do we care?
• The N.E.C. limits the type of items that can be
  installed within a return air plenum space
• In case of fire within the ceiling, they do not
  want toxic smoke being circulated throughout the
  entire building
• The cabling we use can have jackets that would
  emit dangerous fumes if it were ignited
• Plenum rated cable designed for these spaces

14
Plotting a Cable Route
15
Plotting a Cable Route

• How do we install cable if there is no conduit?

16
Plotting a Cable Route

• How do we install cable if there is no conduit?
• Cable must be supported by itself
• Not sharing suspension ceiling supports, etc.
• Bridle rings should be used
• Cable supports can be mounted to
• Bar joists
• I-beams
• Wood trusses
• Slab mounted support wires (like ceiling)

17
Plotting a Cable Route

• Avoid
• EMI sources
• Difficult pathways
• Plot a pull on a floor plan

18
Tools and Methods Cable Pulling
19
Objectives

• List 5 tools for cable pulling
• Explain how cable is removed from a spool
• Describe safety concerns when pulling cable
• Describe pulling tension limits for cable
• Build a cable snout

20
Tools and Methods Cable Pulling
21
(No Transcript)
22
(No Transcript)
23
(No Transcript)
24
Tools
25
Kellum Grip
26
Tools and Methods Cable Pulling

• Clean before you pull

27
Tools and Methods Cable Pulling

• Safety issues
• Gloves to handle fishtape
• Setup barriers around work

28
Tools and Methods Cable Pulling

• Safety issues
• Ladder and scaffolding safety
• Fishtape
• Where is it going?
• Eye injuries

29
Tools and Methods Cable Pulling

• Cable tension limits

30
Cable Snouts
31
Cable Snouts

• Stagger the wires
• Taper the ends

32
Cable Snouts

• Add some tape to hold it together

33
Cable Snouts

• Make a slip knot over the cable about 24 from
  the end

34
Cable Snouts

• Add some tape to hold it in place

35
Cable Snouts

• Make another hoop with a twist and slide it
  down the bundle
• Try to put the knots in the groove between cables
• Repeat 3 or 4 times

36
Cable Snouts

• Tightly wind tape over the bundle and pull string
• Pay close attention to bulky spots add tape to
  smooth it out

Stretch the tape
37
Cable Snouts

• Continue the tape to the tip to complete the snout

38
Cable Snouts

• Label each cable AND spool with a temporary label

39
Questions?
40
ExerciseBuild a Cable Snout