Wire supports and heat shrink tubing are essential for a sound electrical system.

Boats with electrical systems that seldom fail make liberal use of heat shrink tubing, especially in wet areas—which essentially means everywhere on a boat. Battery connections, bilge pump connections, mast wires, windlass wiring and many other applications will work better and require less servicing if you seal wire splices and terminal connections with ALT—which stands for adhesive lined heat shrink tubing.

Marine grade heat shrink tubing offers superior performance.

Hardware store tubing is typically PVC, which is not nearly as strong as the cross-linked polyolefin marine grade heat shrink tubing made by our supplier Ancor. Beyond sealing out moisture, Ancor’s heat shrink marine wire seals create a seal that is impervious to saltwater, oil, acids and sunlight while also providing strain relief to wire connections.

Available Diameters of Heat Shrink Tubing

West Marine offers heat shrink tubing in various diameters to seal very small gauge wire connections all the way up to your battery cable connections. Ancor’s heat shrink tubing shrinks at a ratio of 1:3, meaning it shrinks to 1/3 its original diameter.

Wire Supports

Along with using heat shrink tubing to ensure the integrity of your wire connections, electrical wires must be supported and usually bundled along the length of their run. Cable ties that include a mounting eye are frequently employed for this purpose. Another option are wire clamps and cable clamps, which are C-shaped nylon collars that can be used to bundle and support wires. Stainless steel cable clamps that include a soft rubber lining are also available. Split loom and spiral wrap are frequently used to bundle wires and neaten up an installation.

Thru Deck Wire Seals and Cable Clams

Another concern is how to seal locations where wires pass through a deck. Ancor’s Thru Deck Wire Seal and Blue Sea System’s Cable Clam are two products to consider for this purpose.