Smart Regulator for Yanmar Alternator

[Pete the Cat]

I need help. I have been using my ancient Ample Power Smart regulator (about 20 yo and lots of hours on my previous boat) successfully with my 80 amp Hitachi alternator on my Yanmar for several years with good results. On recommissioning my boat this season, I now have a problem. The regulator kicks in after the 90 second delay and runs the amps up to 50 amp output (used to be higher) for about a minute and then tapers off very fast to 3 or 4 amps of output after running for a couple minutes even though my batteries are down and could use much more. Not sure if there is something simple that would cause this, or if I need a new regulator. The alternator is not hot and neither are the batteries when the amp output drops. Any thing simple to look for??

Ray

[Albro359]

How old are your batteries ? how long since you last charged them ?
You should probably have their capacity tested.
If they are sulphated they will have low capacity and current acceptance so the voltage from the alternator will rise very quickly and the regulator will back off the current to maintain that voltage.
If you have an equalise setting on your regulator you may be able to get some of the battery capacity back.

[smac999]

measure the field voltage coming out of the regulator. if it's 12-13v and the alternator is only putting out 3-4 amps then you probably have a bad alternator.

if the field voltage is low 4-8v (which happens when batteries are full) but the batteries are not full. then something is up with the regulator, or it's voltage sense.

[Pete the Cat]

New batteries and fully charged when they went in just before this use. The Linklite shows good output for a very brief period and current looks appropriate on output, but a good idea to check field current.

[nugeo]

Not sure if you have this one solved but thought I'd add my 2 cents worth.

Be careful of going Balmar external regulator on a Hitachi, I believe the Hitachi is N-Type and the Balmar reg is only suited to P-Type. Sterling Power have two versions of an external alternator regulator than can be set to either P-Type or N-Type. The Hitachi alternator does need the field wire installed but Sterling give a pretty detailed description of how to do this, a good DIY guy should handle it no problem. Doing a full conversion from N-Type to P-Type as described above is quite a lot of work and it renders the internal regulator (used as backup) useless.

I have recently installed the Balmar MC-614 onto our Electromaax alternator and it certainly makes a difference having a smart-charge system, worth doing.

Here's the instructions of how to install the Sterling Power external alternator regulator. BTW: the basic Sterling unit is about one third the price of the Balmar unit but with less programmable features.

http://www.sterling-power.com/images...tors/AR12V.pdf