by Fred Mattera –
Batteries are an integral power source on fishing vessels. They provide power to the vast majority of our pilothouse electronics and are a power source for alarms and startup and shutdown systems for main engines and gensets.
Be sure to install batteries so they are capable of withstanding vessel roll, pitch, and vibration. Otherwise, the slightest motion could cause flexing and breakage of starter cables that could create a fire hazard or lead to a loss of power.
Lead acid batteries require lead drip trays, while alkaline batteries require steel drip trays. These trays should be capable of containing any electrolyte that may be spilled during charging or testing. Batteries should be installed so that they can be inclined 30° without spilling electrolytes.
Keep batteries clean and dry, protecting them from exposure to seawater or fresh water, and provide adequate ventilation to remove dangerous hydrogen gas released during charging. Remember, hydrogen is lighter than air and can accumulate in overhead pockets, creating an explosive hazard. Do not ignore this explosive hazard of batteries. Avoid sparks, flames, electrical switches, and smoking in the battery storage area.
Provide ample room around batteries for ease of removal and access to terminals. Install box covers and/or terminal covers on batteries. If a tool is dropped on an unprotected battery, the result can be arching, shorting-out, or explosion.
All battery connections must be permanent. Don’t use spring clamps or temporary connections.
All vessels should have a back-up battery in the pilothouse with a small trickle charge to provide power to specific electronics such as radios, GPS, and radar for emergencies in case all power is lost.
All cables and wires should have copper conductors of the appropriate size and voltage rating for the circuit. Stranded copper wire should be used aboard vessels because it is more flexible and less likely to fracture due to vibration or movement.
Protect cable runs from the weather to the extent you can. PVC can be used as a conduit to protect cables and wires in areas exposed to weather.
Cables and wires should be supported in a way that avoids chafing or other damage. Wire clips and brackets should be spaced proportionately to maintain straight runs because trouble usually starts at bends. Cables should enter fittings from the bottom so water can’t run along the cable and fill the fittings.
Protect cables in areas subject to mechanical abuse with metal coverings or heavy, thick rubber hoses. It’s always a good idea to scan your wiring and look for areas of wear or chafing. Then replace or provide adequate chafing protection to avoid a fire hazard.
Consider this: The number one cause of engine room fires is faulty or chafed wiring in electrical systems.
Cable runs and fittings in fish holds, net lockers, and lazarettes should be watertight. Cables installed in refrigeration compartments must be suitable for low temperature and high humidity.
Wherever possible, separate cables serving duplicated equipment so that a problem with one does not affect the other. Terminations and connections should be grounded properly and housed in fire retardant enclosures. Terminations, connections, and splices should be vibration resistant and accessible. Use watertight outlets, junction boxes, and caps where electrical components are exposed to weather.
All electric motors must be provided with protection against overload such as breakers and motor starters. Lighting in engine rooms, sorting or packing areas, the fish hold, and deck should have two circuits so a failure of one doesn’t leave the area without light. Lights in these areas should have impact globes or guards.
It’s important to position pilothouse electronics as far as possible from doors and windows to minimize corrosion.
Make sure your vessel’s electronics and electrical systems are serviced and maintained by certified, knowledgeable personnel.
First and foremost, whenever doing electrical work be sure that all circuits involved have been de-energized and tag them to prevent anyone from accidentally re-energizing them. Some equipment or accessories may be energized by more than one circuit, so take care to ensure that all power has been disconnected. If you have any doubts, test the circuit with a voltmeter.
If unusual circumstances make it impossible to de-energize the equipment, every care should be taken to insulate the person performing the work from grounded and energized parts.
Everyone doing electrical work should take the following precautions:
- Never work alone;
- Provide ample lighting and/or have a portable power supply so a failure doesn’t leave your work area without light;
- Take off any watch, rings, chains, other metal articles, or loose clothing that might make accidental contact with live parts;
- Make sure your clothing and shoes are as dry as possible;
- Use insulating material to cover grounded metal to which you may be exposed;
- Consider covering the metal portion of hand tools with insulating material;
- Wear rubber insulated gloves;
- Use eye and face protection; and
- Have someone standing by to turn off the power.
To sum up, always take a practical and cautious approach when working on electrical systems.