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jv20 · 14-12-2012, 10:09

I'm looking to replace an old pro mariner charger 60 amp, I am questioning which amperage or if I can go down to a 50. The boat has 2 - 8D batteries plus a group 27 for the genset. any suggestions would be appreciated thanks

**David M** · 14-12-2012, 10:30

I had to look it up, this is a twin engine diesel powerboat people, which means it has engines with alternators that are running when the boat is underway.

It depends on your house load at the dock and how much patience you would have if you had to wait to charge up two dead 8-D's. There is no right or wrong answer with this. I would definitely not go any lower than a 50 amp charger for two 8-D's, otherwise you could be waiting a long time for a recharge or not have enough DC power at the dock without having to run your generator dockside.

Are one of your 8-D's dedicated to starting the mains?

Since your group 27 is a start battery for your generator, it should be isolated from your house system so that you are never dead in the water underway, therefore it does not need to be part of the calculation.

I have a 100 amp inverter/charger for a house bank with three 8-D's. It has always been more than what I need.

I think you can get by on a 50 amp charger if are not getting close to drawing 50 amps of DC dockside. This figure I think is your bottom line and 50 amps may or may not be enough for a 42 foot power boat. Turn on every DC load that you might have on at night at the dock with the generator off and see if you get near 50 amps of power drain.

River Cruiser · 14-12-2012, 11:56

I have 2 8D batteries, 1 dedicated house & the other start for the twin diesels. Also have 1 group 27 generator start. Had a the old ProMariner 60 amp 3 bank charger, I would have to add water to the 8Ds once every 4 to 6 weeks. Decided to upgrade to a newer 3 stage charger, called ProMariner they have loyalty program & I bought a 1260c3 60 amp charger. It is programable for battery type & in over 2 years I have added less than a quart of water to the 8Ds. ProMariners loyalty program saved me about $200.00 on the best price I could find from any dealer, had to give the model & serial # of my old charger to get it. Plus I sold the old one for $100.00 to a friend that needed a charger. If you have a old ProMariner this is the best way I've found to upgrade to modern technology that means less maintenance & longer battery life.

ranger58sb · 14-12-2012, 15:04

Quote:

Originally Posted by jv20

I'm looking to replace an old pro mariner charger 60 amp, I am questioning which amperage or if I can go down to a 50. The boat has 2 - 8D batteries plus a group 27 for the genset. any suggestions would be appreciated thanks

a) Stay with 60 amp or larger.

b) Call ProMariner.

-Chris

jv20 · 19-12-2012, 11:24

Thank you for all the responses, I'm doing a 60 and I will try the customer loyalty approach first and see where it goes

jv20 · 19-12-2012, 12:52

Just an update on the pro mariner cust appreciation program, they quoted me $620 last week and would give me $20 off only, not much of a program, I found a 1260p for $489 at anchor express. Go there instead

**Dockhead** · 19-12-2012, 13:16

That's 480a/h of capacity, so 60 amps is a pretty small charger -- 12.5%C. On a motor cruiser that might be ok if you are always charged up from the alternators and just use the charger to keep them topped off at the dock. In that case, the difference between 50 and 60 amps is not important.

If, however, you will be spending time on the hook and need to charge with a generator, then you would benefit from a charger closer to 20% C, which would be around 100 amps.

DotDun · 19-12-2012, 13:19

Quote:

Originally Posted by jv20

Just an update on the pro mariner cust appreciation program, they quoted me $620 last week and would give me $20 off only, not much of a program, I found a 1260p for $489 at anchor express. Go there instead

Buy the same charger direct from the manufacturer for $449.

Marine Battery Charger - Sterling Power ProCharge Ultra- Power Factor Corrected (PFC) PCU - 60amp

**David M** · 19-12-2012, 13:20

I agree with Dockhead about having a 100 amp charger for charging up on the hook.

DotDun · 19-12-2012, 13:39

Quote:

Originally Posted by Dockhead

That's 480a/h of capacity, so 60 amps is a pretty small charger -- 12.5%C. On a motor cruiser that might be ok if you are always charged up from the alternators and just use the charger to keep them topped off at the dock. In that case, the difference between 50 and 60 amps is not important.

If, however, you will be spending time on the hook and need to charge with a generator, then you would benefit from a charger closer to 20% C, which would be around 100 amps.

With 450ah house bank/60amp charger, when I charge from genset, I engage a battery combiner between the genset start battery and the house bank and that adds an extra 35amps from the genset alternator (used to charge the genset start battery). When absorption draw gets below shorepower charger capacity, I'll release the combiner and let the 'smarter' charger take it all. Most of the time I'm not charging from 50% down, hence the period of time I need a bigger charge is normal pretty short (<30 minutes).

My battery combiner is the Victron Cyrix and I have toggle switch control (both on/off and emergency mode) of it from the nav station.

ranger58sb · 20-12-2012, 14:19

Quote:

Originally Posted by jv20

Just an update on the pro mariner cust appreciation program, they quoted me $620 last week and would give me $20 off only, not much of a program, I found a 1260p for $489 at anchor express. Go there instead

That's useful, thanks for posting. The nice prices I've heard about before (with no specifics) were always about replacing a defective or failing unit, so I was under the impression it was the tech support guys who underwrote the deep discounts (if any). Didn't ever have specifics, though; all anecdotal.

-Chris