Captain's Choice Marine SurveyOrillia, Ontario |
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Cheap battery boxes with plastic webbing for securing them are not the best choice, but anything is better than nothing at all. If using boxes doesn't appeal to you the minimum you must do is keep the batteries clean, put plastic caps over the terminals for safety, secure the batteries from any movement and have trays under them to collect electrolyte. The location of the batteries is also important as they must be in a dry area. For the most part the engine room is a good choice and you usually have lots of room to select a good area for storage. You must be kept them high enough to prevent even high bilge levels from reaching them, so at least 12-18" above water areas is a good idea. Securing them to the decking is very important as well as installing them in an area where they are easy to service. Another problem I have often found is direct wiring connections to the batteries and inline fuse use. There is no reason why wiring should be attached directly to the terminals. Such a setup tells me the person who installed the circuit was either too lazy or uninformed to do it the proper way, resulting in the main panel being bypassed with possibly no fuse protection or at best with an inline fuse.
My only real exception to the rule is the direct wiring of a bilge pump which is sometimes a wise idea. Having to change a fuse in emergency situations when the pump is most needed can be problematic. The chance of having an electrical fire caused by a bilge pump is minimal. Lastly, sizing of the batteries you use is very important as well as having the proper type. There are basically two kinds, cranking automotive style batteries and deep cycle storage batteries. The minimum size battery that companies like Mercury and Volvo require a minimum of 1000 cranking amps for their ECU units according to their service bulletins. You will need a battery for each engine as well as at least one storage battery for needs off shore and at anchor for equipment like a stereo or DC refrigerator. Normal batteries that you get at ship stores or chandlerys are usually 650 - 750 cranking amps so pay attention when purchasing. |
Another problem area that I run into almost every day is battery issues. The main cause for battery discharge is improper installation and poor circuitry. Batteries with top mounted terminals can generate a large enough current flow between the terminals when they get wet and dirty to discharge the battery. It is imperative to keep a battery dry, clean and protected and the best way to accomplish that is with a good quality battery box that is well secured to a deck. This will also protect the battery from accidental short circuits as required by ABYC safety rulings.
Inline fuses are usually not labeled for their circuit use and in an emergency the likelihood of finding or reading the fuse is not very high, especially in the dark or in rough sea conditions. Even wire leads to the main panel should come off the battery switch, not the batteries. When I find these problems I usually recommend that the wiring be rerouted through a correctly installed secondary panel.
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