Smart regulator interfering with Volvo Penta motormanagement?

[zeevantijd]

For the past 7 years a smart external regulator (Mastervolt alfa-pro) was in charge of our alternator. The main reason for installing this external regulator in the past was the composition of our battery banks: 1x55Ah AGM for starting, 2x55Ah AGM for bowthruster&winch, and 3x150Ah Gel for service. After filling up the batteries at 14.1 - 14.4 V, this smart 3-stage regulator cuts down the voltage in the so-called floating phase to 13.6 V to prevent excessive gassing and prolong battery-life.

Unfortunately we had to repower this winter. We replaced our Volvo Penta MD22P-B by a Volvo Penta D2-75F, which comes with a Mitsubishi 115A alternator. This alternator has an internal 'dumb' regulator with sense wire that simply keeps the output voltage at 14.4 V. During longer passages we are sometimes forced to motorsail for 24-48 hours. This will overcharge our gelbatteries for a very long period.

To overcome this problem I would like to let a smart external regulator like our previous Mastervolt alfa-pro take control over the new alternator. For that purpose the internal regulator would have to be disconnected and the field of the dynamo externalized. Volvo Penta however, claims that their original alternator should not be tampered with, since motormanagement "senses/uses data" from the alternator and would be compromised by any change in this alternator. Does anybody have experience in installing a smart external regulator on the 115A Mitsubishi alternator of the new Volvo Penta D2 series? Any problems with motormanagement?

[Kettlewell]

It's hard to believe the alternator's internal regulator doesn't taper off the voltage somewhat during longer runs, but something like the Sterling Battery to Battery charger or their intelligent battery isolator might be the answer to your problem. Hook up the alternator to the start battery and then charging will go through the Sterling to your house bank.

I have no first-hand experience with this equipment.

[Lake-Effect]

Originally Posted by zeevantijd

This alternator has an internal 'dumb' regulator with sense wire that simply keeps the output voltage at 14.4 V. During longer passages we are sometimes forced to motorsail for 24-48 hours. This will overcharge our gelbatteries for a very long period.

I'm still learning the finer points about battery chemistry, but a dumb regulator that limits charging voltage to 14.4v probably won't overcharge your battery. I don't have docs at hand to back this, but I recall from a previous discussion with MaineSail that he confirmed 14.4v as the desired charge cut-off voltage.

In fact I expect the reverse is true - it's hard to get a complete 100% charge from a simple voltage regulator. Only if the 'dumb' alternator's output voltage is higher than 14.4v into a fully charged battery is it likely to overcharge. I believe that inefficient charging is the most common reason for going to a better alternator regulator.

To overcome this problem I would like to let a smart external regulator like our previous Mastervolt alfa-pro take control over the new alternator...

Volvo Penta however, claims that their original alternator should not be tampered with, since motormanagement "senses/uses data" from the alternator and would be compromised by any change in this alternator.

Volvo-Penta must know that many cruisers opt for better alternators. I would ask them to tell you specifically what alternator signals the "motormanagement" system requires from the alternator. 'm expecting the answer is tach pulses, which you will need to confirm are available from any alternator/regulator upgrade.you want to do.

[zeevantijd]

Originally Posted by Lake-Effect

a dumb regulator that limits charging voltage to 14.4v probably won't overcharge your battery. Only if the 'dumb' alternator's output voltage is higher than 14.4v into a fully charged battery is it likely to overcharge.

You are right about the desired charging voltage of 14.4v. Even for AGM and gelbatteries this is true. But after topping them of for 1-2 hours at this voltage, the charging voltage should be decreased. At 14.4v you can hear small gasbubbles in any gelbattery. That is why they are called VRLA batteries: valve regulated. To a small extend this will not hurt them, but going on like that for >24 hours will shorten battery life.

Most AC battery chargers therefor use a 3-step (or even 4-step) charging program. Smart regulators can provide the same program for your alternator. This is nice and slightly more efficient for wet batteries, but a 'virtual must' for VRLA batteries like gel or AGM.

Thanks for your input on the tach pulses. I will look into that.

[smac999]

I'm not sure what info they would be getting other then possible a tach signal, and an alternator working alarm.

tach should still work with ext reg. I've issues with Volvo alternator alarms before. I just disabled it so the dash would never alarm if the alternator stopped working (probably ground the signal wire, can't remember off hand)

I would just ditch the gel batteries... and get some agms. gels are a pain. how are you charging the other batteries? are you using acr's / vsr's between the agm starter / thruster batteries and the gel house? because that is another problem. as the voltages should be different for gel and agm and they shouldn't be combined

[zeevantijd]

Originally Posted by smac999

I would just ditch the gel batteries... and get some agms. gels are a pain. how are you charging the other batteries? are you using acr's / vsr's between the agm starter / thruster batteries and the gel house? because that is another problem. as the voltages should be different for gel and agm and they shouldn't be combined

I'm using a Mastervolt Battery Mate IG-1603 to separate my 3 battery banks. While battery isolators are conventional diode splitters, the Battery Mate's technology is electronic and includes mosfets (transistors, i.e. no voltage drop).

I have considered ditching the gel batteries as well, taking AGM's instead. Their specs allow for a higher voltage during the absorption phase of the charging process. Supposedly gel batteries have a longer life, can perform more charging cycles. For my service bank, I don't need the Cold Cranking Amps that AGM's can supply. How well do AGM's tolerate 14.4v for 24-48 hours? After all, they are valve regulated lead acid batteries as well, and therefor susceptible to gassing. The charging voltage of AGM's should drop to 13.6v as well after topping them up, isn't it?

[smac999]

yes agms should be floated as well. but putting 14.4v into an agm will be better then putting 14.4v into a gel. gels should be charged at 14.1. so you need an external regulator that has a gel setting. charging at 14.1. which means you're 2 agms will be charging at 14.1 and be under charged.

(your onboard battery charger should also have a gel setting, and will also be under charging your agms)

really every battery on the boat should be the same. you can't just throw gel batteries onto a boat. everything on the boat needs to be setup for gel. when they made agm batteries after gel were already out they learned this lesson and made the voltage levels similar to flooded so they could just be swapped in place. (though optimal agm settings are a bit off, but close enough to work)

the external reg is definatlly better no matter which way you go.

[zeevantijd]

Does anybody have experience in installing a smart external regulator on the standard 115A alternator of the new Volvo Penta D2 series? How did you disconnect the internal regulator and bring out the field wire? Any problems with Volvo motormanagement?

[colemj]

The problem with the new Volvo's is that they continually set off multiple alarms if the charging system is not as expected (meaning modified in any way - including a non-Volvo alternator). So modifying the stock alternator to take an external regulator is very simple, but the boat will not stop beeping and flashing at you if you do so. I believe disabling the alarms causes other problems.

Balmar and others have been trying to get the necessary voltage/signal information out of Volvo so they can modify their alternators, but Volvo has refused to help.

Mark

[zeevantijd]

Originally Posted by colemj

So modifying the stock alternator to take an external regulator is very simple, but the boat will not stop beeping and flashing at you if you do so.

Thanks Mark, that is useful information. I'll ask both Mastervolt (nice external 3-step regulators) and Volvo Netherlands for their view on this.

[crzhors]

Hello zeevantijd, Have you learned anything from Volvo or Mastervolt
about this issue? I have the same issue with a 2007 D20-40. This model has a tach sensor on the flywheel housing,so tach signals shouldn't be a prob but the computer sensors/alarms may be. Hope to hear more.Thnx.

[zeevantijd]

Originally Posted by crzhors

Have you learned anything from Volvo or Mastervolt about this issue? I have the same issue with a 2007 D20-40. This model has a tach sensor on the flywheel housing,so tach signals shouldn't be a prob but the computer sensors/alarms may be. Hope to hear more.Thnx.

Hi CRZHORS,
Mastervolt, both HQ and their resellers, keep up avoiding to answer this question. Volvo Penta does not really have a HQ to turn to. They referred me to their dealers. I contacted 5 of those. Just like Mastervolt, 4 of them either did not understand the problem, stated 14.4v was just fine for a gel battery, or suggested to us a diode for voltage dropping.
The 5th (both VP and Mastervolt dealer) claims to have experience in modifying the alternator and installing an external 3-step regulator without causing massive Volvo alarms. I will take the boat there next week and give them a try at it. I will keep you informed about the proceedings...

[zeevantijd]

Originally Posted by crzhors

Hello zeevantijd, Have you learned anything from Volvo or Mastervolt
about this issue? I have the same issue with a 2007 D20-40. This model has a tach sensor on the flywheel housing,so tach signals shouldn't be a prob but the computer sensors/alarms may be. Hope to hear more.Thnx.

Hi CRZHORS and other contributers,

Hereby the proceedings: The alternator was slightly modified by a specialist company (http://www.lasaulec.nl). They externalized the field wires and disabled the internal Mitsubishi regulator. The external regulator was then installed following the installation instructions by Mastervolt.

So far, so good. Volvo Penta motormanagement gives no problem or alarm at al. Charging runs efficient, but more important, I can manually set the level for absorption (14.25V) and floating phase (13,40V) to prevent excessive gassing and prolong gelbattery-life.

I can really recommend this to other Volvo Penta D2 users. Thanks for all your advise, Marein

[Edwin Curacao]

To where did you connect the battery light wire (brown) and the "exiting" wire (Blue/red) the triggers my battery alarm on dash I think.

I'm installing the balmar regulator, have it running but as soon as turning on regulator and start charging the alarm starts. if regulator off no alarm....

Now connected Blue/red wire unconnected and dash light to balmar regulator dash out

[Edwin Curacao]

Volvo Penta D2-55 Wiring Diagram from workshop manual.