80A Yanmar Alternator Externally Regulated
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This is not a cheaply built, Chinese made, re-badged automotive alternator and a dumb internal regulator. This is an exact fit externally regulated 80A alternator intended to replace the Yanmar / Hitachi LR180 series, and other Hitachi's, found on many small Yanmar engines. It is an exact fit.
I worked with my manufacturer for many months to source the right parts, test it and ensure it could perform at the price point I desired. Many of the components we tested for this alternator failed in less than an hour at full output at room temp.
This Hitachi cased alternator is hand assembled in the USA to my own stringent specifications to ensure a quality product. Yes, some of the components are made overseas but we sourced the best components we could possibly find to meet the value to performance ratio I was looking for. This alternator fills the gap between a true high performance alternator (see my other custom alternator offerings) and the factory alternator. It was designed to meet a price and performance niche not available to boaters previously.
The CMI-80-ER comes standard with a tachometer output wire (stator tap) for Yanmar diesels that run the tachometer sense off the alternator. Not all Yanmar engines drive the tachometer from the alternator, but some do. The CMI-80-ER is set up for external regulation only. It has no internal regulator. The vertical plug of the "T" connection is the FIELD terminal to be driven by an external regulator.
-Identical fit to the Hitachi/Yanmar 3.15" saddle mount case.
-80A Rated with good high idle performance.
-Machine wound stator of 14GA top quality magnet wire means better cooling and higher temperature tolerance.
-Precision machined rotor and slip rings for greater contact at all RPM.
-Tighter tolerance of stator/rotor gap for better performance. The specs are better than the very expensive Hitachi branded alternators..
-Rotor is precision balanced to .025 ounce inches. Industry norm is .050 - .090. This means smoother operation and less harmonics.
-Upgraded higher performance diode rack.
-Brushes are high copper content composite not run of the mill carbon brushes. This yields superior conductivity and considerably longer brush life.
-Ready to accept an external regulator (I recommend Balmar regulators).
-1/2" billet machined single v pulley, not cheap stamped steel. (3/8" available upon request)
-Isolated ground for steel or aluminum boats or for using a shunt in the negative path..
-Hand assembled in the USA (Note: some internal components are non US made but carefully chosen)
-Built to marine standards for ignition protection.
-Every CMI-80-ER comes with a performance testing certificate showing the tested output curve. The alternator pictured here produced 97A when cold.
"B-" = Negative:
The CMI-80-ER has an isolated-ground rectifier. This means the case of the alternator is not your negative terminal. The rectifier utilizes two terminals to carry the negative load current. You can connect to either of the negative terminals which have been bused together using 6GA wire. DO NOT wire your battery negative cables to the case of this alternator.
This blue wire is to be used if your Yanmar tachometer is sensed from the alternator.
The vertical of the "T" plug is the field. The horizontal of the "T" is unused.
This terminal can be used for the alternator temp sensor.
"B+" = Positive Output:
This terminal is the alternator output and should be fed directly to the house battery bank including a fuse within 7" of the + battery terminal at 150% of the 80A rating. Minimum fuse size is 120A. Minimum wire size should be 6GA.
CMI-80-ER + ARS-5 Typical Diagram
This is the correct wiring for Balmar ARS-5 regulator when used with the CMI-80-ER. If your tachometer is sensed from the alternator (not shown in diagram) follow the Balmar ARS 5 instructions.
IMPORTANT: For proper battery voltage sensing the regulator BLACK and regulator RED must be connected as close to the battery terminals as possible. The regulator red/power/B+ wire must be fused within 7" of the battery positive terminal or its bus.