Electrical Bus Bar Torque Specs

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Electrical bus bar torque specs.

Bus bar and terminal connections. Connections can create electrical noise power quality issues by vibrating and creating arc at the connection. Up facilities engineering electrical interior facilities. Torque for bus bar lugs is specified by lug size.

I am a firm believer in using manufacture torque requirements i have been in the mining industry as electrical troubleshooter for 30 years and over 90 of failures caused by tightening methods i also will move the wire around and torque again this has proven to help in maintaining torque specs when wires are moved into position to close cabinet. Typical hardware for bolting listed lugs to bus bars. Use the torque specifications in. Zinc plated to retard corrosion and installed with the proper torque this hardware has a long history of satisfactory performance with both copper and aluminum bus bars.

Tm 5 683 nawac mo 116 afjman 32 1083. Ensure you know the torque specification. Knowing required ampacity determine possible bus bar dimensions from the table. All of the major companies who manufacture electrical components have torque specifications for their equipment ask for it.

Diameter of bolt used should be compatible with hole in tang. Hexagonal bolt grade minimum sae grade 2 unc coarse thread. Then check table 1 to verify that size selected has the necessary ampacity. Importance of torque in bussing a critical concept in understanding bus lug torque specifications is the fact that the pressure of the lug connection has more to do with lowering the resistance of the electrical connection than the size of the lug itself.

Plated sae or stainless steel flat washers to be used on both sides. For 60 hz current table gives bus bar cross sections which will probably be large enough for ampacities within each range. Reduce torque by 20 when cadmium plated bolts are used. Typical busway installation.

Have the bus bars cleaned annually with clean dry. Ensure your electricians own and know how to use a torque wrench.