A torque wrench should always be used on bus bars and cable connections. Unless you have the one time nuts that shear at the proper torque. I make my j-men mark all connections with a sharpie to indicate that 1 they actually tightened the bolt or nut. And 2 to verify that the connection has not been compromised. I also make them place a label in the gear with their name, date, employee# and the # of the wrench they used. The only gear failure I have ever seen was actually caused by over torquing. They were single bolt Square D bars in a 1600 amp setup. Field rep told me that the bars would actually warp away from each other and lose surface contact.