Ac Battery Charger???

[Ed]

Batteries, etc

Will send you what pictures that I have, as well as the part number for the combiner...We have a 3J engine, was repowered in '97 by the privious owner...So the hp has never been an issue with us...73Ed S/V MYST

 

[Ed Schenck]

2QM20 Battery Wiring.

I think Richard's question about the 2QM20 was for Jacksonville Ed. Huron Ed has a '79 2QM20 but with the Hitachi 55-amp alternator replacing the 35-amp. Know that anything bigger than 35-amp has new wiring because it uses an exciter voltage to "charge" the magnetic field. I have the new wiring diagram if you make that change.I think 75-amp is about max for the 2QM20. We are already underpowered and it takes horses to make amps. Better to build the battery bank large enough to handle your weekends.I have three 95 amp-hour gels in the house bank tied to switch position #2. I have a 900 CCA AGM battery for the starter which I never use. Switch is always on #2. A battery combiner keeps the starter battery topped off.All the batteries are in the starboard locker. The AGM and one gel on the hull in the original location and two gels on the shelf behind the icebox. I may relocate those two on the shelf to further aft under the coaming. That area is so hard to store anything useful but there is a locker that would be covered back under there.Also find "Yaga Wiring" in the photo forum for a good battery wiring reference.

 

[Ed Schenck]

2QM20 Battery Wiring.

I think Richard's question about the 2QM20 was for Jacksonville Ed. Huron Ed has a '79 2QM20 but with the Hitachi 55-amp alternator replacing the 35-amp. Know that anything bigger than 35-amp has new wiring because it uses an exciter voltage to "charge" the magnetic field. I have the new wiring diagram if you make that change.I think 75-amp is about max for the 2QM20. We are already underpowered and it takes horses to make amps. Better to build the battery bank large enough to handle your weekends.I have three 95 amp-hour gels in the house bank tied to switch position #2. I have a 900 CCA AGM battery for the starter which I never use. Switch is always on #2. A battery combiner keeps the starter battery topped off.All the batteries are in the starboard locker. The AGM and one gel on the hull in the original location and two gels on the shelf behind the icebox. I may relocate those two on the shelf to further aft under the coaming. That area is so hard to store anything useful but there is a locker that would be covered back under there.Also find "Yaga Wiring" in the photo forum for a good battery wiring reference.

 

[Richard McDonald]

Ed and Ed.....

Huron Ed, thanks. Where did you get the Hitachi 55-amp alternator from? Do you have a part and/or model #? Although, we do mostly use the boat on weekends now with a 2 week summer cruise on lake Michigan, I am planning to build the electrical system to be self sufficient for longterm salt water cruising. I will considerer re-powering in a few years or earlier, if I come across a good used Yanmar, so 55-amp max will be it for now on the 2QM20.NC Ed, Thanks, I did received your emails and replied with a few more questions.RichardS/V Rhapsodie

 

[Ed Schenck]

Richard --> E-Bay

I have saved so much money by shopping on E-Bay. There is a dual-foot Hitachi 70 amp on there right now(Related Link). And that seller states that he has several used parts. Hitachi-55s should be easy to locate because so many Yanmar owners have upgraded. I like them because I do not have to mess with a separate regulator.Also watch "Gear Here" on this site(under Boats For Sale) and other marine forums.The numbers on the alternator are: LR155-20 129772 - 77200 12V - 55A

 

[Steve Weinstein]

WARNING - LONG RESPONSE: Bob, I've

a very similar set up to you on my 1981 H33. I've got a 2002 Yanmar 2GM20 (replaced my original 1981 2QM15), 110 AmpTech high output alternater, Balmar MC-612 external regulator, a pair of L16 6-volt batteries (370 AHr/ea.)in series giving me a 370 AHr 12-volt house bank, a Group 24 starting battery, 80W Solar Panel with a ProStar-15 (Morningstar) charge controller and the Xantrex/TruCharge 20+ shorepower charger.Ed is correct (as usual!!!)in that the high output alternaters will rob many hp from the engine. At full output that alternater robs 6 hp of the available 18. The Balmar regulator has two work-arounds, however. It has two spade connectors designed to accept leads from a temperature sensor (battery or alternater). If you bridge those connectors you cut back the alternater output by half. I did that and put a single-pole on/off switch so I can choose between full output and half output depending on how much power I need from the engine. You can also put an on/off switch in-line on the brown wire from the accesory post of the ignition key switch to the regulator. If I throw that switch to the off position I completely kill the alternater output and retain all my 18 hp. The nice thing is that these set-ups do not damage the alternater.Also, the starting battery gets charged through the Echo Charger drawing current from the house bank. This works well since when the engine is started it'll be running for about 30-40 minutes (off the mooring and out of the mooring field, etc...) I'm pushing enough amps out to recharge the starting battery. Once the starting battery is re-charged (not very long) then all amps go into and stay in the house bank.This setup works great for me since I can charge both banks while at the dock, bring both banks up to full while motoring, and get a nice top-off/replacement charge from the solar panel while sailing.I'm attaching a half-assed schematic of my system. Feel free to drop me a note off-line if you want more clarification.