Grounding Steel Towers

Steel towers obviously should be grounded for lightning protection whether or not grounding is needed for efficient antenna operation. Steel is a difficult metal to electrically bond to. Satisfactory connections can be made using exothermically welded lugs, compression lugs, or crimp lugs, but only if these rules are followed: 1) Never use a single-hole ground lug, because it is apt to come lose if jarred. Ground lugs should be secured by at least two bolts. 2) Tinned-copper ground lugs should be used, because tin reduces corrosion between copper and steel. 3) Use the nuts and bolts supplied by the lug manufacturer. 4) Torque them according to lug manufacturer recommendations. Insufficient torque increases resistance because no surfaces are perfectly smooth. Excess torque increases resistance because of lug warping. 5) Carefully clean and dry both lug and steel before attachment, because tin and steel both corrode when exposed to air and corrosion increases contact resistance. ©2005 Tigertek, Inc. All rights reserved.

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