INTRODUCTION

Whenever aluminium cable is terminated on copper bus bar or copper contact and aluminium lugs are used then contact between terminal lug and copper bus bar being of dissimilar metals leads to galvanic action. Also if copper lug is used then contact between aluminium cable and barrel of copper terminal lug the galvanic action takes place. Thus in order to prevent and avoid galvanic action it is always advisable to use copper-aluminium Bi-Metal lugs.

CONSTRUCTION

In Bi-Metal lugs barrel of the lug is of aluminium and the head or palm of the lug is of copper.
This ensures contact between aluminium cable to terminal lug is of aluminium and contact between terminal lug to copper contact is of copper.
Thus contact between dissimilar metal is avoided and contact between similar metal is established.
Thus Bi-Metallic or galvanic action is completely eliminated and hence technically sound and durable joint is achieved.
Electrolytic copper head / palm is friction welded to electrolytic aluminium barrel.
If aluminium cable is to be joined with copper cable then Bi-Metal in line connectors are to be used.