Do I need a regulator for AGM batteries?

[jimrjohnson5325]

Hi, I just re-powered my boat and have a 125 AMP Yanmar Alternator. My house bank has 3 AGM Batteries. I also have two 140 Watt Solar Panels. Do I need a special regulator?

[belizesailor]

Assuming both your alternator and solar have good regulators, then no...the two regulators will sort it out.

[Sailmonkey]

Originally Posted by belizesailor

Assuming both your alternator and solar have good regulators, then no...the two regulators will sort it out.

However if your solar regulator doesn't have an agm setting, or the ability to be adjusted for agm. And your yanmar alternator is stock with an internal regulator, then you really should get an alternator regulator and a solar regulator that allow for agm care and feeding.

[belizesailor]

Originally Posted by Sailmonkey

However if your solar regulator doesn't have an agm setting, or the ability to be adjusted for agm. And your yanmar alternator is stock with an internal regulator, then you really should get an alternator regulator and a solar regulator that allow for agm care and feeding.

Yes, needs to be "good" regulator with applicable programming options.

[witzgall]

Agm batteries an accept a very high amount of current when in the bulk stage of charging. Even more so with tppl agm batteries. This will max out your alternator, asking it to charge at the absolute highest average it can, for as long as it takes to charge them. This can put a huge stress on the alternator. It will often short life the alternator, as it literally burns itself up. Now if it is internally regulated, that regulator will limit the current as it heats up. The result will be much longer charging. This is where an external regulator comes into play. It is not heated up by the alternator working hard. However, you need one with an external temperature sensor attached to the alternator, so it dials down as the alternator heats up. This will mean the most efficient charging possible, while still protecting the alternator.

Chris

[DeepFrz]

Originally Posted by witzgall

Agm batteries an accept a very high amount of current when in the bulk stage of charging. Even more so with tppl agm batteries. This will max out your alternator, asking it to charge at the absolute highest average it can, for as long as it takes to charge them. This can put a huge stress on the alternator. It will often short life the alternator, as it literally burns itself up. Now if it is internally regulated, that regulator will limit the current as it heats up. The result will be much longer charging. This is where an external regulator comes into play. It is not heated up by the alternator working hard. However, you need one with an external temperature sensor attached to the alternator, so it dials down as the alternator heats up. This will mean the most efficient charging possible, while still protecting the alternator.

Chris

Actually a good external regulator will allow you to dial back the alternator output so the alternator doesn't over heat at all. Waiting for the alternator to over heat before dialing back the output is not the best way to go about it. Balmar's small engine and belt saver settings allow you to use the alternator in a safe way and to prolong the life of expensive equipment.

[Frugal]

You haven't mentioned if your solar panels have a regulator?
Unregulated output from your panels will quickly destroy your AGM batteries if the panels output exceeds your consumption.
An mppt regulator with the appropriate boost / float settings is far cheaper than replacing your batteries.
Cheers

[jimrjohnson5325]

I have a Solar Boost 2000E (25 Amp Max power point tracking solar charge controller) made by Blue Sky Energy. What Regulator would you recommend for AGM batteries. Do I need to have the new 125 Amp Yanmar Alternator modified? Is this plug and play such that I can do the work myself? Thanks Jim Johnson SV Lisken. Presently in Montreal repowering.

[jimrjohnson5325]

I find that Balmar makes a "smart ready" kit replacement regulator for the Valeo 125A Alternator that came on the 3JH5E Yanmar. I'll check it out tomorrow. Jim Johnson SV Lisken

[witzgall]

Originally Posted by DeepFrz

Actually a good external regulator will allow you to dial back the alternator output so the alternator doesn't over heat at all. Waiting for the alternator to over heat before dialing back the output is not the best way to go about it. Balmar's small engine and belt saver settings allow you to use the alternator in a safe way and to prolong the life of expensive equipment.

At least with the Balmar 6xx series with alternator temp probe, the output is dialed back before it reaches damaging temperatures, so it does not overheat. You could use a regulator that allows you to dial it back, and then experiment by monitoring the temp and setting accordingly. But the temps in an engine room, and in different situations could be different, no?

Bottom line, using a temp sensor will ensure the highest safe charging, regardless of conditions. The only other option I think makes some sense is to install a MUCH bigger alternator, and then derating.

Chris

[jimrjohnson5325]

Everybody, Thanks for the responses. I bought a Balmar Smart Ready Retrofit for the Yanmar 3JH5E Equipped with Valero 125A Alternator. I could not find a distributor to deliver in a timely manner. I called Balmar directly and they were very helpful! I should receive the kit in 3 days to Montreal. It has Alternator mod kit with Alternator and Battery temp sensors. I got the MC-614. $600 but save my equipment. http://www.balmar.net/smart-ready-retrofit-for-yanmar/