Before installing your new alternator, please take a moment to consider the following guidelines for safe alternator installation and operation. Failure to follow these guidelines could result in injury or damage to your vessel’s electrical system.
1. Always disconnect your batteries and turn your battery switches to their “OFF” positions prior to installing your alternator.
2. Remove any loose fitting clothing or jewelry which could become entangled in your motor or other machinery.
3. Wear ANSI-approved safety glasses or eye wear.
4. Ensure that the engine has cooled sufficiently before beginning installation.
5. DO NOT install your high-output alternator without ensuring that system wiring is sufficient to handle increased amperage loads.
6. Be sure that your work area is properly ventilated and that no fuels or solvents are present in and around your work area.
7. DO NOT operate your charging system without proper fusing. Failure to do so could result in severe injury and/or damage or loss of your vessel. DON’T take chances with fusing.
8. DO NOT attempt installation while using alcohol or medications which could impair your judgement or reaction time.
9. Use the right tool for the job. Use of improper tools could result in damage or injury.
10. Take time to read the manual. Equipment damage and possible injury may result from an incomplete understanding of the proper installation and use of the alternator.
Sizing Battery Cables
Battery cable size must meet the increased output capacity of your new alternator. The easiest method for determining the best cable size for your system is to compare your new alternator’s rated amperage output and the ROUND TRIP length of the cable running from the alternator to the battery being charged, and back to the alternator via ground to the chart at right. Cable length requirements may also be calculated with the formula CM=K x I x L/E (whereas CM represents the circular mil area of the conductor, K represents the mil-foot resistance of copper, I represents current, and L represents the length, in feet, of the round-trip cable run and E represents voltage drop in volts). When using this equation, a K constant of 10.75 indicates copper's mil-foot resistance and voltage drop should be calculated at 3% (0.36V for 12V, 0.72V for 24V). 94-Series Alternators
Large case 94-Series Alternators are designed to provide 165 or 210 amps at 12 volts, or 140 amps at 24 volts. Mounting is a 2"single-foot Delco-style mount. Alternators in the 94-Series feature isolated ground terminals, external regulation and 12-pole stator output.
1. Positive Output Terminal - Must be connected via properlysized cable to the battery or batteries being charged. Cable size is determined by alternator output and length of cable run. See Page 3 for wiring size chart.
2. Negative Terminal (Ground) - Must be connected to system ground via properly sized cable. Cable size is determined by alternator output and length of cable run. See Page 3 for wiring size chart.
3. Stator Output - Unrectified source of AC voltage which can be used as a signal for an electric tachometer. In 12-volt systems, stator terminal will connect to WHITE wire. In 24-volt systems, the Stator Wire will connect to the ORANGE wire in the regulator wiring harness.
4. External Field Wire (BLUE) - Connects to external voltage regulator via wiring harness.
An unsupported cable may damage the positive or negative terminals, resulting in damage to alternator, regulator and wiring. Ensure that cables are adequately supported to supply strain relief. Grounding
Alternator models designated as Isolated Ground (IG) feature an independent ground terminal that’s isolated from the alternator case. Isolated Ground alternators are used in applications where the engine is not desired to be a part of the grounding system. This is commonplace in steel or aluminum hull boats, or with engines that depend on sophisticated electronic ignition systems. In other applications, isolated grounding simply ensures that the alternator is sufficiently connected to system ground. The alternator’s ground cable should be the same size as the alternator’s positive output cable.