Second alternator or DC to DC charger

[Neil Ramsey]

The Wakespeed WS100 is what I am using and it is only $373 USD in 24V. Smarter than I am and good enough for most boats. US made and excellent support.

 

[Jeff F]

I'm not fearful of bulk charging from an alt
But I see no reason to spend bulk coin to do it when it seems there are other far more affordably ways of achieving same

I think you've demonstrated a high fear threshold here when it comes to these systems

As others have sensibly pointed out, a needs assessment is critical. If a high charge rate is not required there is a compelling case for adding a small DC-DC charger to maintain the house bank and leaving the rest of the system as is. Maybe $500 for materials, even down under. If solar or plugin or a genset normally meets liveaboard needs it's an effective inexpensive solution IMO.

Sent from my moto g play (2021) using Trawler Forum mobile app

 

[David Griffiths]

Quote from Simi
"Just realised the OP made no mention of big bank or 24v so that could be the difference
Large frame 24v with J180 mount alts are silly money here."

Current configuration:
1000CCA sealed L/A start
660AH 12V AGM house bank
600w solar No genset.
65Amp OEM alternator on the JOHN DEERE
Dodgy second 120Amp alternator (crappy bracket too much flex, belts misaligned and dusting)
Now removed and looking to charge the house system.
Thruster and Anchor winch are 24V powered from 2 AGM batteries. Vetus thruster system includes a built in 12 to 24v converter to charge the 24v batt bank.
Options: Upgrade the OEM alternator to 120Amp unit and add another DC to DC charge system to manage the house bank. (Carry a second 120Amp alternator as a spare)
OR
Add another 120Amp alternator (on a properly designed bracket) to manage the House
bank charging, probably with an external regulator.
Easiest is to add the DC to DC charger (compared to fabricating another alternator bracket)
Big thanks to everyone sharing their ideas and perspectives.

 

[catalinajack]

Has anyone found a detailed "how to" guide for converting an internally regulated Delco to an externally regulated configuration? The 130Amp Ample Power externally regulated alternator on our boat died last year and I found a decent 120 amp Delco17SI in my pile of car parts. At the moment I have a 55A internally regulated Delco charging the 660A golfcart house bank.... (the tachs run off the alternator)

Alternatively, it is possible to just leave the internal regulator in place and run the 17SI through the external regulator?

Or...can I easily tie in a temperature signal to the 17SI (with internal regulator)? Where do I purchase a temperature sensor?

marinehowto.com

 

[Rufus]

Thanks. I checked out that website a while back. It has a conversion writeup for a Leece-Neville, but not for a Delco.

 

[Tomas]

I installed the Sterling Alt to Batt charger in 2016. It does a great job keeping the start bank and 675 AH house bank charged.


https://www.sterling-power-usa.com/sterlingpowerusa12volt-210ampalternator-to-batterycharger.aspx

 

[JDCAVE]

Thanks. I checked out that website a while back. It has a conversion writeup for a Leece-Neville, but not for a Delco.

Find a good starter motor/alternator shop and talk to them for a start. There is a good one local to me (Brighouse Electric) and their advice and help along the way has been invaluable to me.

Jim

 

[Jeff F]

Current configuration:
1000CCA sealed L/A start
660AH 12V AGM house bank
600w solar No genset.
65Amp OEM alternator on the JOHN DEERE
Dodgy second 120Amp alternator (crappy bracket too much flex, belts misaligned and dusting)
Now removed and looking to charge the house system.
Thruster and Anchor winch are 24V powered from 2 AGM batteries. Vetus thruster system includes a built in 12 to 24v converter to charge the 24v batt bank.
Options: Upgrade the OEM alternator to 120Amp unit and add another DC to DC charge system to manage the house bank. (Carry a second 120Amp alternator as a spare)
OR
Add another 120Amp alternator (on a properly designed bracket) to manage the House
bank charging, probably with an external regulator.
Easiest is to add the DC to DC charger (compared to fabricating another alternator bracket)

How important is the charge rate for the house bank? That would drive my decision. It's a big difference between 20-30 amps through a small DC-DC charger and 90+ through a dedicated alternator.

Also does the motor have a serpentine belt? That limits the upper size on a single alternator.

 

[David Griffiths]

Hello Jeff
Charge rate is a valuable question. Depends on distances moved each day/engine run time vs other battery inputs, in my case solar. Here in Australian latitudes, solar seems to be a reasonable option.
Serpentine belt driving OEM 65amp alternator.

In the first instance my plan is to upgrade the alternator to a 120amp unit.
Solar currently delivering 600w
Use DC to DCC chargers to recharge House and Thruster/winch systems.
Will my system be in balance then? Possibly...if not my thoughts are to then add an external regulator to the 120amp alternator.
If still inadequate.. 1. Cut back power usage 2. add the second alternator 3. OTHER OPTIONS??
Thankyou all for your contributions, most valuable and appreciated
Forum thoughts??

 

[mvweebles]

Hi David. With all due respect, if you can find a decent marine electrician to at least help you with your design, I think you would save money and have a more productive system. At the least, this really needs sketches and diagrams. Better would be a qualified professional who can view the boat, spaces and offer an informed opinion on general layout and configuration.

I've designed and installed several off-grid systems over the last several years, but I recently decided to hire a specialized EE to assist in design for an an usual application to power a remote boat lift vs running 240vac to the location. He was invaluable in specifying equipment and battery storage. Saved me quite a bit of money vs where my head was going.....

Peter

 

[Mike GB32]

Rufus-
There's a fairly detailed discussion about converting a Delco Remy 28SI alt to external voltage regulator on the Cruiser Forum. Not sure that'll help you.
https://www.cruisersforum.com/forums/f14/converting-delco-28si-to-external-regulation-204361.html

 

[Rufus]

Thanks Mike. I'll check it out.