Cooper Bussmann CT02MAN manual Egc

Page 29

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Discontinuous Joints

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Require Bonding

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bonding Jumper Not

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Required For Rigidly

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

For Qualifying Facilities

 

 

 

 

 

 

 

 

 

 

 

Bolted Joints

 

 

 

 

 

 

 

 

 

 

 

Bond

 

 

 

EGCs in the Cables or

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

EGC Cables Are Not

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Required If Rating Of The

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Feeder Overcurrent Device

 

 

 

 

 

 

 

 

 

 

 

Conduit

 

Permits Using The Tray

 

 

 

 

 

 

 

 

 

 

 

 

 

For the EGC

 

 

 

 

 

 

 

 

 

 

 

Three Phase

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Motor Installation

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Motor Control Center

 

 

 

 

 

 

 

 

 

Bond

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

EGC In

 

 

 

 

 

 

 

 

Switchgear

 

 

 

 

 

 

 

 

 

 

 

 

 

Cable

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Transformer

 

 

 

 

 

EGC

 

 

 

 

 

 

(Solidly

 

 

 

 

 

 

 

 

 

Building Steel

 

 

Grounded

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Secondary)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Ground Bus

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bonded To

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Enclosure

 

 

Lightning

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Protection

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Grounding

 

 

 

 

 

 

 

 

 

 

 

System Ground

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Correct Bonding Practices To Assure That The

Cable Tray System Is Properly Grounded

If an EGC cable is installed in or on a cable tray, it should be bonded to each or alternate cable tray sections via grounding clamps (this is not required by the NEC® but it is a desirable practice). In addition to providing an electrical connection between the cable tray sections and the EGC, the grounding clamp mechanically anchors the EGC to the cable tray so that under fault current conditions the magnetic forces do not throw the EGC out of the cable tray.

A bare copper equipment grounding conductor should not be placed in an aluminum cable tray due to the potential for electrolytic corrosion of the aluminum cable tray in a moist environment. For such installations, it is best to use an insulated conductor and to remove the insulation where bonding connections are made to the cable tray, raceways, equipment enclosures, etc. with tin or zinc plated connectors.

See Table 250.122 on page 51 for the minimum size EGC for grounding raceway and equipment.

Cable Tray Manual

Cooper B-Line, Inc

27

Image 29
Contents Cable Tray Manual Page Table of Contents Introduction Cable Tray Safety Features WHY Cable TRAY?Cable Tray Space Savings Cable Tray DependabilityMaterial Cost Savings Cable Tray Wiring System Cost SavingsDesign Cost Savings Cost Cable Tray vs. Conduit Installation Cost Time SavingsMaintenance Savings Cooper B-Line, Inc Scope AN IN-DEPTH Look AT 2002 NEC Article 392 Cable TraySteel Ventilated Trough Center Supported Cable Tray Definition. Cable Tray System Uses Permitted. a Wiring MethodsCable Tray Materials Cable Tray Manual Uses Permitted. B In Industrial Establishments 392.3B1b 392.3B1a392.3B1c Uses Permitted. C Equipment Grounding ConductorsSealing and Drainage. E Cable Seals, Class 1, Division 2 Uses Permitted. E Nonmetallic Cable Tray 502.4B3. Nonincendive Field WiringUses Not Permitted Construction Specifications. a Strength and RigidityCable Tray Manual Construction Specifications. C Corrosion Protection Construction Specifications. B Smooth EdgesConstruction Specifications. D Side Rails Construction Specifications. E FittingsNomenclature Construction Specifications. F Nonmetallic Cable TrayInstallation. a Complete System Installation. B Completed Before Installation Installation. D Covers Installation. C SupportsInstallation. H Exposed and Accessible Installation. G Through Partitions and WallsInstallation. F Cables Over Volts Installation. I Adequate Access Grounding. a Metallic Cable Trays EGC Grounding. B Steel or Aluminum Cable Tray Systems Temperature Rise Test Cable Installation. B Fastened Securely Cable Installation. a Cable SplicesCable Installation. D Connected in Parallel Cable installation. C Bushed Conduit and TubingSheet 3, Example 392.9A1 392.9A2 392.9E2 392.9F2 Single Diameter Inch Conductor Inches Channel Size AWG Technically Undesirable Installation Interpretation #1 Cable Tray Wiring System Design and Installation Hints Cable Tray Manual Cooper B-Line, Inc Fireproofing Cable Tray Cable Tray AccessoriesCable Tray Maintenance and Repair FRP Cable TRAY. Thermal Contraction and Expansion13B is 128 F. The 125 F line in Table Cable Tray Manual Cooper B-Line, Inc Appendix Pages See Page 29 for Temperature Rise Test illustration Circuit Arrangement for Rigid Conduit Temperature Rise Tests Example NEC .9A1 Example NEC .9A2 Example NEC .9A3 Example NEC .9B Appendix Sheet Start Sizing Cable Tray Per NEC Here Cable Tray Sizing FlowchartYes Ladder Or Vented Trough Line Series Project InformationFiberglass-Vinyl Ester Resin Ventilated Non-Ventilated Cent-R-Rail Wire Basket TrayCable Channel Cooper B-Line, Inc Cable Tray Manual Line Wire Management Resources Ask the Experts