Smart regulator for QSB 5.9 Alternator

[Paul Bellefontaine]

I have a 2006 QSB 5.9 with what looks like the standard Delco alternator. The electronic display shows it to be putting out a fixed 13.1 volts. I have an 8D AGM deep cycle start battery and 2 8D AGM deep cycle house batteries. They should be charged at 13.5 volts float voltage.
1) Is there a standard Cummins alternator and regulator that would allow for adjustable output voltage? Even better an external smart regulator that would quick charge the batteries through bulk charging before settling down to the float voltage?
2) A respected after market direct fit?

3) The start battery is connected to the house with a Blue Seas 120 Amp ACR automatic charging relay. The alternator output is going to the start battery. Does it make sense to have the output go directly to the house bank where (voltage would be lowest and) it should be most needed? Any tricks or traps in moving the alternator output to the house bank?

Many Thanks

Topic

[Rob Schepis]

Yup… that’s why these DVMs are such a great add-on..

https://www.sbmar.com/articles/installing-digital-volt-meters-dvm-boat/

[Scott Lambert]

I also have a QSB 380 with smart craft gauges. Smart craft says 13.1 v while actual alternator voltage is 14. Worth checking alternator voltage with different meter.

[Fireisland1]

I have same engine with Smartcraft gauges. Sweep gauge shows 13.2 volts. Digital guage in display shows 13.1v. This is while at 1800 RPM. Fluke meter {calibrated } at batteries and remote digital display both show 14.2v. Is this a case of Smartcraft not being so smart. You may have the same issue

[Author]

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