GenMaax Saddle Mount, 12 Volt, 250A Alternator, Remote Rectified


Introducing the GenMAAX Saddle Mount Alternator 12 Volt, 250A, ElectroMaax brings to the marine market a compact, remote rectified alternator, ideally suited for large battery banks, including Lithium, AGM, and Gel Batteries. This alternator boasts an anodized frame with a special coating for saltwater resistance and enhanced heat dissipation. It delivers the power of a large-case alternator in a small-case design that fits most marine engines. With its innovative remote rectification, which positions the rectifier up to 48” away from the engine, the system significantly reduces heat and simplifies wiring by eliminating connections at the back of the alternator — promoting efficiency and ease of use for most cruisers’ daily energy needs.

SKU: GM-SM-12-250A-RR Categories: ,


For boaters with large battery banks – especially Lithium batteries – ElectroMaax has introduced a remote rectifier to our GenMAAX alternator 250 12 V and 165 24 V models. This Super High-Output alternator/generator is all you need to survive, covering all energy needs on your boat. The frame is hard black anodized with a special salt water resistant coating that enhances heat dissipation, which is critical for any alternator over 160 amps.

The bolt-on replacement, 250 amp GenMAAX gives you all the output of a large-case alternator in a small case that fits 99% of marine engines.

Fits these Yanmar engines: 2GM • 2GM20 • 2GM20-YUE • 2GM20F • 2GM20F-YUE • 2GMF2YM15 • 3GM • 3GM30 • 3GM30F • 3GMF • 3HM • 3HM35 • 3HM35F • 3HMF • 3JH2 • 3JH2-TE • 3JH3 • 3JH3-E • 3JH4 • 3JH4-E • 3JH5 • 3JH5-E • 3YM20 • 3YM30 • 4JH • 4JH-E • 4JH-HTE • 4JH-TE • 4JH2 • 4JH2-DTE • 4JH2-E • 4JH2-HTE • 4JH2-TE • 4JH2-UTE • 4JH3-E • 4JH3-HTE • 4JH3-TE • 4JH4 • 4JH4-AE • 4JH4-E • 4JH4-HTE • 4JH4-TE • 4JH5 • 4JH5-E • 4JH110 • 4JH80 • 4JH57 • 4LHA6LY • 2QM15 • 2QM20 • 3QM30 • 3QM30(F)

Specifically developed to meet the technical demands of the new generation AGM, Lithium and Gel Batteries, the GenMAAX 250 super-high-output alternator/generator produces a continuous 195 amps covering most cruisers’ daily energy needs in very short order. Remote rectification has been in use for decades in industrial applications and removing the rectifier out of the rear of the alternator and placing it a few feet away, has many benefits. By far the single biggest benefit is that over 50% of the heat has been removed from the alternator.

Only the heat generated by the stator remains. In addition, the air space now available due to the removal of the rectifier which allows the twin fans attached to the rotor to work more efficiently by greatly enhancing heat dissipation too. With the remote being up to 48” away from the alternator and engine, the device can be located next to the batteries in a generally more cooler and dryer place.

Now there are no connections needed at the back of the alternator. In essence we are splitting the alternator in half. This allows for the output of a large frame alternator in a small case alternator frame. Due to no wiring at the back of the alternator (now done at the face of the Remote Rectifier) makes the wiring hookup much simpler too.


  • genmaax-installation-manual.pdf


  • genmaax-250a-12v-datasheet.pdf

  • genmaax-remote-rectifier-datasheet.pdf

Become a Partner

Provide your customers with the most technologically advanced marine power products.

Marine Smart Energy

The choice for advanced DC products at "direct from the manufacturer" pricing!

Contact Info

5552 King St.

Beamsville, ON L0R 1B3

"The best marine products I've ever purchased for my vessel - and amazing support too!"

Customer Support

If you are not able to find an answer to your problem, contact us and we’ll return your message in a timely manner.

©2024 Marine Smart Energy - All Rights Reserved
Return PolicyShippingWarrantyPrivacy PolicyContact Us
May Promotion