Marine Wire

 by Allied Wire & Cable, Inc.

The marine environment is a hostile one for electrical wire. Wire used on board a marine vessel will potentially be exposed to numerous obstacles, such as salt water, sunlight, heat and other outside hindrances. All electrical wires are not constructed to endure the problems associated with marine conditions and therefore will not be suitable wiring on boats or ships. In these situations, marine wire or boat cable may be necessary.

Marine wire, boat cable, and marine primary wire are terms you may have heard used in reference to electrical wiring for boats or marine vessels. Wiring specified as "marine" or "boat" is different in several ways from other types of electrical wire, such as power wire used in the home, or automotive wire, etc. A main difference is that the conditions surrounding marine installations require marine wire and boat cable to perform better than other wires designed chiefly for land use.

A marine wire is specifically designed and engineered for the electrical wiring of boats and is intended for all possible uses abroad a ship. Marine wire may be distributed to the pleasure boat and commercial marine industries and is often used by boat builders. The term "boat cable" may often be used interchangeably with marine wire or marine cable. Boat cable usually refers to general electrical wiring used on a boat. Marine wire that may fall into the sweeping category of "boat cable" often starts as a single conductor cable. Extra wires are added from there into one cable, consequently creating multi conductor boat cable.

Because of the demanding marine environment, approved marine wire usually possesses a copper conductor. In addition, the jacket of the cable will most likely have been tested for flammability safety. The jacket and the insulation should be rated water resistant.

The most frequently requested single conductor boat cable styles are marine primary wire and marine battery cable. The cables are extremely similar. The main factor that differentiates the two is the AWG size of the cable. According to General Isles Marine, single conductor boat cable in sizes 16 AWG up to 8 AWG are widely known as primary wire sizes. The larger single conductor marine cables ranging from size 6 AWG up to 4/0 AWG are known as battery cable sizes.

Often times, marine wire and boat cable provided by a manufacturer or distributor will meet the requirements of UL, SAE, Coast Guard, ABYC, and NMMA. The American Boat and Yacht Council (ABYC), the United States Coast Guard (USCG), the National Marine Manufacturers Association (NMMA) and the Society of Automotive Engineers (SAE) have developed safety standards and guidelines for marine electrical installations specifically serving manufacturers, technicians, and even boat owners.

Corrosion is a primary cause of electrical failures on a boat. In order to avoid the common problem, marine wire and boat cable are built to resist quick decay. In both wet and dry conditions, marine wire needs to behave consistently in order to perform properly. Marine wire, boat cable and marine primary wire may possess PVC insulation for added defense against the elements. After all, they need all of the help they can get.

The remaining links will examine the various types of marine wire and boat cable on the market today.

Common Types of Marine Wire

Marine Primary Wire (Tinned Copper)

Marine Primary Wire may also be listed as Tinned Primary Wire. The copper conductor will usually possess a tin coating which causes the strand to be called "tinned copper." Tinned copper marine primary wire is built to reduce corrosion and prevent electrical failure.

Marine Primary Wire (Tinned Copper) can be used in 105ºC marine applications, in the internal wiring of electrical equipment and for general circuit wiring. It is employed for electrical connections in the marine and automotive environments where a tinned conductor is preferred. The marine primary wire may additionally be utilized for motorcycles and other applications requiring a high temperature primary wire. Tinned copper marine wire performs well in all marine environments, even in saltwater.

You may see marine primary wire listed as UL 1426 marine grade wire. Most brands of tinned primary wire will meet the requirements of the US Coast Guard and ABYC, as well as others.

Marine Primary Wire (Bare Copper)

Marine Primary Wire (Bare Copper) can be used in 105ºC marine applications, in internal wiring of electrical equipment and for general circuit wiring. The marine primary wire shares many of the same applications and properties as tinned primary wire. However, the conductor is bare copper instead of tinned copper.

SAE Primary Wire

SAE Primary Wire is General Purpose Thermoplastic (GPT) insulated primary wire that corresponds to SAE specifications, generally specifications J1128 and J378. SAE Primary Wire may be used for general purpose marine and automotive applications. It usually has a temperature range of -20ºC to 105ºC and voltage rating of 50 volts.

Flat Boat Cable

Flat Boat Cable is a multi-conductor marine cable that can be used for marine or brake cable. The boat cable usually meets UL Standard 1426 and UL Style BC-5W2. Flat boat cable also may meet DOT Coast Guard specs. The boat cable has a PVC insulated multi-conductor.

Round Boat Cable

Round Boat Cable is much like flat boat cable. However, round boat cable makes for easy installation where tight, jagged spaces are present. Many installers of boat cable favor round cables because they are easier to arrange. Additionally, round boat cable may be used for harsh environments.

Marine Battery Cable

Marine Battery Cable generally has a temperature range of -20ºC to 105ºC and a voltage rating of 50 volts. The battery cable also resists oil, fuel and acid. Marine battery cable is designed to survive the harsh marine environments. The cable normally has a high strand count cable with tin plated copper stranding. Marine battery cable may be used in battery installations.