Anyone know anything about alternator? - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > General Interest Forums > Gear & Maintenance
 Not a Member? 
  #1  
Old 10-26-2008
Senior Member
 
Join Date: Feb 2008
Posts: 148
Thanks: 1
Thanked 0 Times in 0 Posts
Rep Power: 7
preservedkillick is on a distinguished road
Anyone know anything about alternator?

I'm trying to figure out how long it will take my 50amp alternator to recharge by batteries.

I've got 220 amp house battery, say it's down to 50%, how long do I need to run the engine to fully recharge?

Are there formulas for this sort of thing???
__________________
Preserved Killick


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Seagrass
Boothbay Harbor, ME
Alberg 30:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
  #2  
Old 10-26-2008
erps's Avatar
the pointy end is the bow
 
Join Date: Aug 2006
Location: La Conner, Washington
Posts: 6,064
Thanks: 1
Thanked 19 Times in 19 Posts
Rep Power: 9
erps will become famous soon enough erps will become famous soon enough
Do you have an externally regulated three stage charger, or the stock internal regulator? That factor alone will make all the difference in the world.
__________________
Ray
S.V. Nikko
1983 Fraser 41
La Conner, WA


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


Boating for over 25 years, some of them successfully.
Reply With Quote Share with Facebook
  #3  
Old 10-26-2008
Senior Member
 
Join Date: Feb 2008
Posts: 148
Thanks: 1
Thanked 0 Times in 0 Posts
Rep Power: 7
preservedkillick is on a distinguished road
Just the stock internal regulator.
__________________
Preserved Killick


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Seagrass
Boothbay Harbor, ME
Alberg 30:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
  #4  
Old 10-26-2008
sailingdog's Avatar
Telstar 28
 
Join Date: Mar 2006
Location: New England
Posts: 43,291
Thanks: 0
Thanked 8 Times in 8 Posts
Rep Power: 13
sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice
Figure that the battery bank will accept pretty much maximum amperage until it hits the 85% charge level...so from 110 amp-hours to 190 amp-hours or 1.6 hours... as the charge level increases from that point... the charge acceptance rate will drop... so it may take another eight-to-ten hours or so to get up to 100% as a rough guess...so you're looking at about 10-12 hours over all.

However, since you only have the internal regulator, you'll probably start frying the batteries after hour three or four, since it won't drop the voltage and amperage the way an intelligent three-stage charger would.
__________________
Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
Reply With Quote Share with Facebook
  #5  
Old 10-26-2008
Senior Member
 
Join Date: Oct 2006
Location: Virginia
Posts: 722
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 8
badsanta is on a distinguished road
How do you know its down? What are you using?
Reply With Quote Share with Facebook
  #6  
Old 10-26-2008
sailingdog's Avatar
Telstar 28
 
Join Date: Mar 2006
Location: New England
Posts: 43,291
Thanks: 0
Thanked 8 Times in 8 Posts
Rep Power: 13
sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice
If you have a voltmeter, you can roughly estimate this... a fully charged 12 VDC system is about 12.6-12.7 volts... at 50% it'll be about 12.1-12.2 VDC... at 0% it'll be 11.6 VDC or so.
Quote:
Originally Posted by badsanta View Post
How do you know its down? What are you using?
__________________
Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
Reply With Quote Share with Facebook
  #7  
Old 10-26-2008
Senior Member
 
Join Date: Feb 2008
Posts: 148
Thanks: 1
Thanked 0 Times in 0 Posts
Rep Power: 7
preservedkillick is on a distinguished road
Quote:
Originally Posted by sailingdog View Post
Figure that the battery bank will accept pretty much maximum amperage until it hits the 85% charge level...so from 110 amp-hours to 190 amp-hours or 1.6 hours... as the charge level increases from that point... the charge acceptance rate will drop... so it may take another eight-to-ten hours or so to get up to 100% as a rough guess...so you're looking at about 10-12 hours over all.

However, since you only have the internal regulator, you'll probably start frying the batteries after hour three or four, since it won't drop the voltage and amperage the way an intelligent three-stage charger would.
So,

Does a 50amp alternator put out 50 amps/hour? Is that how they are measured? 10-12 hours! Wow, one night of fun and then there's hell to pay.

Is an internal regulator that bad that it would severely overcharge a battery?
__________________
Preserved Killick


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Seagrass
Boothbay Harbor, ME
Alberg 30:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
  #8  
Old 10-26-2008
Senior Member
 
Join Date: Feb 2008
Posts: 148
Thanks: 1
Thanked 0 Times in 0 Posts
Rep Power: 7
preservedkillick is on a distinguished road
I don't know it's down. I'm just setting up, and installed 2 6v batteries in series as the house bank. I'm just thinking of how this will play out. I hate motoring. Yet I don't have any other means of recharging.

I also set up the BlueSea ACR thanks to the tips from you guys. I don't yet have any way to easily tell the state of my batteries, other than the volt-meter test.
__________________
Preserved Killick


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Seagrass
Boothbay Harbor, ME
Alberg 30:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
  #9  
Old 10-26-2008
sailingdog's Avatar
Telstar 28
 
Join Date: Mar 2006
Location: New England
Posts: 43,291
Thanks: 0
Thanked 8 Times in 8 Posts
Rep Power: 13
sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice
Of course, the actual output of the alternator really depends on the engine RPMs... if the engine is going too slowly, it won't put out the rated amperage.

Ideally, you'd have a three-stage external regulator on the alternator, and some alternate form of charging—either solar or wind. If you keep the boat in a slip, you'd probably want to have a shore power setup and a good three-stage AC-powered battery charger.
__________________
Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.

Last edited by sailingdog; 10-26-2008 at 07:56 PM.
Reply With Quote Share with Facebook
  #10  
Old 10-26-2008
Senior Member
 
Join Date: Dec 2002
Posts: 118
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 12
chuck711 is on a distinguished road
Best way is just to run engine and monitor results

Best way is just to run engine and monitor results.
I had 5 (12 volt , 525 total amps or so) batteries aboard.
Only had a 35 amp alternator. It worked fine to recharge.
Run for an hour and check results.
Reply With Quote Share with Facebook
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On



All times are GMT -4. The time now is 12:55 PM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012