Frequently Asked Questions

Click on a question below to view the answer. If you have any additional questions feel free to contact us.

I have been told that I need a dual pulley to drive a high output alternator. Is this true?

No. 98+% of all Powermax alternator installations (up to 125 amps) typically use a single drive pulley & single belt.

Do I have to purchase a separate regulator to operate my Powermax alternator?

In most cases, the answer is... Yes . All Powermax externally controlled alternators require a regulator. We offer a Powermax Basic Regulator that if purchased at the time of your Powermax Alternator order is available at a special price. We also offer a Smart Regulator for those desiring the maximum power output from the Powermax Alternator. The exception to the rule is this - If you are purchasing our Powermax LT alternator, these Powermaxes are internally regulated and do not require an external regulator to operate as their regulator is built in.

Which regulator is best suited for my needs?

It all depends on how you use your boat & how much power you require. The Powermax Basic Regulator works well for those who spend 15-30 minutes motoring out of the harbor at the beginning of the weekend, and 15-30 minutes when they return. Usually in this scenario, the daily usage is fairly low and the 30-60 minutes of Powermax charge time is enough to keep the batteries charged. For those who do a lot of long term motoring or need lots of charging power, a smart regulator is preferred. This regulator goes through a 3 step program of charging, to get the batteries properly charged, but not overcharged. Based on battery bank feedback, the regulator decides when the battery is full and drops into a float mode, which is the stage that reduces the charging voltage to a maintenance level.

How long does a Powermax Alternator take to install?

Our customers have told us that their Powermax installation time has ranged anywhere between 1 and 4 hours, with 2 to 3 hours being quite typical.

I do not have an ammeter on my boat, so how do I know if my Powermax Alternator is working?

A voltmeter (built in or hand held) can give you a very basic idea of performance. If the voltage reading at the battery bank increases when you run the engine, the Powermax Alternator is producing power and charging the battery(s). The voltmeter does not however, give us any indication as to how many amps we are producing. For that reading, you do need an ammeter. We build & offer a 0-150 Amp DC Ammeter for just this application.

Why does my new Powermax Alternator charge so much faster than my old alternator did?

The standard alternator was only designed to replace the minimal power it took to start the engine. Period. Its design was never intended to, and can not support the heavy volume of amp/hours that is typically consumed from the deep cycle batteries of a large house battery bank. Because the Powermax is over-built & designed to provide lots of charging current at low engine RPM (at anchor or while moored), we can actually charge anywhere from 4-6 times faster than the standard alternator, which keeps the engine run time to an absolute minimum. Faster charging means many things. It means less engine running time, less fuel consumption, less engine wear & tear, less noise, less smell & less heat below deck .

My engine is only an 18 HP diesel. Will a Powermax Alternator work for me?

The Powermax 80 amp alternator was designed specifically with the smaller HP engines in mind. For those in the 15-20 HP range.

What wire gauge do I use to connect my new Powermax Alternator up?

Generally we recommend you use #2 AWG cable for wiring both the output and the ground connections of the Powermax. This will ensure that all of the current your Powermax Alternator produces, will travel efficiently & safely (without line losses along the way) to your battery bank. Dont short-change yourself on power by not using the proper cable needed to deliver that power to your batteries. Hamilton Ferris Co makes up custom cables for just this purpose, all the time. Call us with your needs.

I keep hearing that I should use a Spike Stop with my Powermax Alternator. What is it & do I really need one?

A Spike Stop is a low cost spike or surge suppressor that protects the diodes of the alternator, and / or the voltage regulator. Voltage surges can be caused by a number of incidents such as lightning in the area (and not necessarily a direct hit), or commonly by someone accidentally switching the selector switch from one battery bank to another and passing through the OFF position as they do. That split second in the OFF position causes a high voltage spike to travel through the system & generally the diodes in the alternator, or the regulator itself, will fail. In short, the Spike Stop is cheap insurance, protecting against an expensive regulator or alternator repair.

My Powermax Alternator was just installed, and I notice that it is running quite warm. Is this normal?

This is very normal especially if your battery bank is low & needs a hefty charge. The Powermax Regulator senses this & is telling the Powermax Alternator to bulk charge the battery bank. This process produces tremendous charging current, and the by-product of a high charge rate is heat. The Powermax can run at 200 degrees F, so although at tmes it may seem warm to hot, it is doing exactly what it is designed to do. Your batteries and your wallet will appreciate it too! Batteries that are properly charged will last much longer, often times many years longer, than batteries that are routinely discharged but not properly brought back to a fully charged state.

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