About boat upgrades to the charging system. In general most people look at the charging system in terms of a series of discrete components. A charging system must not be viewed as a collection of components, but as an entire electrical power supply system, the boats power station or onboard electricity utility. The typical charging system comprises a considerable number of elements and these are summarized.
Make a simple drawing. It is a good idea to trace out each circuit on your boat, and draw in each component and mark each connection on it. As a minimum the average system will have 4 main positive circuit connections, 4 main negative circuit connections, 4 control circuit connections, 2 changeover switch contacts, a meter shunt, the alternator, the regulator and the batteries.
1. The alternator
(which includes several integral components such as the brushes, brush holders,
sliprings, bearings, diodes and stator windings).
2. The regulator,
(which may be integral or separate).
3. The DC positive
circuit, (which includes the connections at the alternator and battery, and the
changeover switch or isolation switch).
4. The DC negative circuit, (which includes the connections at the alternator and battery, the cable back to the battery, and the meter shunt if fitted). In addition the engine block also becomes part of the negative circuit, along with alternator bracket, holding bolts etc.).
5. The batteries.
The math of this
simple analysis is that there are an average total of 14 connection points plus
the alternator, regulator and battery that can directly impact on the starting
system, plus the human element, the “boat owner”.
Each point represents
a single point failure with subsequent total system failure, with no apparent
redundancy. For this exercise wind,
water and solar panels are considered extra or supplementary charge sources, as
are diesel generators with AC battery chargers.
These however can be factored into the redundancy provisions. The operational factors also must be considered, the human factor in particular. If a battery changeover switch is opened or fails during operation, the alternator can be destroyed, and it is more common than one might think.
A starting system must also be viewed as not simply a collection of series connected components, but as a system. The typical starting system comprises the following elements
1. The DC positive circuit, (which includes connections at the battery, the isolator or changeover switch, the solenoid connection, and solenoid contacts, the starter motor (which includes several components such as brushes, brush gear, commutator, bearings, windings).
2. The DC negative circuit, (which includes connections at the battery, engine block, the cable back to the battery, the engine block, and the meter shunt if fitted).
3. The engine control system (from panel and includes key switch, stop and start buttons, wiring harness, connectors, fuses etc.).
4. The preheating system (which includes the heating elements or glow plugs, and the connections, relays and connectors).
5. The engine starting battery.
The math of this analysis is that there are also a total of around 14 connection points plus the solenoid coil, the starter motor, the battery, the key switch that can directly impact on the starting system and prevent the system functioning. Each point represents a single point failure with subsequent total system failure, with no apparent redundancy. If a person persists with turning over an engine that will not start they may also burn the starter motor out. There are other less common scenarios.
The key to minimizing failure or mitigating the effects of failure is the provision of redundancy amd this is a great boat upgrades. Redundancy in simple terms is having backup systems as part of the design, so that on one system failing the other will provide the charging or starting. In the average single engine boat, normal systems design and installation rarely incorporates any redundancy on charging, power or starting systems. In most commercial shipping, this is a basic premise in all systems design. There are several methods for improving redundancy and the following are the easiest and most economical to carry out. While not easy on some yachts there are some measures that can be implemented. This includes carrying appropriate spares, it is quite astounding how few people carry spare alternator or starter motor, a cheap investment I would have thought. Boat upgrades also means upgrading the spares inventory.
1. An engine powered DC generator. Compact units are available which are small diesel powered alternators
2. An AC generator with mains powered battery charger. The on board generator with a battery charger offers the best battery charging source, however its relatively expensive and has space and weight constraints limiting it to larger yachts although there are some very small compact units such as those from Fischer Panda.
3. A combination of wind, solar and water powered charging systems. They are supplementary only as they depend on environmental factors, if the sun doesn't shine and the wind doesn't blow then no charging is possible but you have to be unlucky to have more than temporary interruptions. All about boat maintenance and boat upgrades to electrical systems.