alternator questions - SailNet Community
 
LinkBack Thread Tools
post #1 of 5 Old 05-13-2013 Thread Starter
Senior Member
 
SSBN506's Avatar
 
Join Date: Apr 2008
Location: New Brunswick Canada
Posts: 173
Thanks: 2
Thanked 3 Times in 3 Posts
Rep Power: 8
 
alternator questions

I have a few questions about an alternator. I have a m25 on a 1986 Catalina 30
tall rig. My first question is what is the amp output of that engine alternator?

My second question is about how it is wired. I have a clipper bm-1 battery
monitor I just installed. I have everything working for the most part as it is
monitoring my house bank and can pick up the drains of all the electrical stuff
and the change from solar. What I am wondering is how to get it to se the
alternator.

My setup is as follows. I have the battery switch that has bank 1 and 2 all and
off. On bank on 1 have two batteries one is 85ah and 140ah connected together.
Bank 2 is the starting battery.

The bmr picks up everything from bank 1 just fine. I can but haven't wired it to
bank 2 yet. My question is where will the alternator put it's charge? Does it
just put it back into the starting battery or is it wired to the electrical
panel so it will change all banks? Do I have to change the dale to all to charge
all battery's from the alternator?
SSBN506 is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 5 Old 05-13-2013
Maine Dub
 
34crealock's Avatar
 
Join Date: Dec 2012
Location: Maine
Posts: 215
Thanks: 27
Thanked 17 Times in 16 Posts
Rep Power: 3
 
Re: alternator questions

It probably charges whichever battery(s) are selected. 1, 2, or both.
34crealock is offline  
Quote Quick Reply Share with Facebook
post #3 of 5 Old 05-13-2013
Learning the HARD way...
 
eherlihy's Avatar
 
Join Date: Jan 2007
Location: Boston / Ft Myers Area
Posts: 4,087
Thanks: 159
Thanked 110 Times in 107 Posts
Rep Power: 9
 
The stock alternator on an M25 outputs 55A...

Based on the other modifications, I doubt that you have a stock alternator.

BTW - both batteries in the same bank should be identical...


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

USCG Licensed OUPV Captain, ASA 101/103/104/105/106/118 Instructor - Also certified in Marine Electrical Systems


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
eherlihy is offline  
Quote Quick Reply Share with Facebook
post #4 of 5 Old 05-13-2013 Thread Starter
Senior Member
 
SSBN506's Avatar
 
Join Date: Apr 2008
Location: New Brunswick Canada
Posts: 173
Thanks: 2
Thanked 3 Times in 3 Posts
Rep Power: 8
 
Re: alternator questions

Quote:
Originally Posted by eherlihy View Post
The stock alternator on an M25 outputs 55A...

Based on the other modifications, I doubt that you have a stock alternator.

BTW - both batteries in the same bank should be identical...
Thanks for the alt info. What is the risk/disadvantage of batteries of different ah connected. The battery setup minus the battery monitor are from the previous owner.
SSBN506 is offline  
Quote Quick Reply Share with Facebook
post #5 of 5 Old 05-14-2013
Senior Member
 
Stu Jackson's Avatar
 
Join Date: Jul 2001
Posts: 902
Thanks: 0
Thanked 15 Times in 14 Posts
Rep Power: 15
 
Re: alternator questions

Quote:
Originally Posted by SSBN506 View Post
I have a few questions about an alternator. I have a m25 on a 1986 Catalina 30
tall rig.

1. My first question is what is the amp output of that engine alternator?

2. My second question is about how it is wired. I have a clipper bm-1 battery
monitor I just installed. I have everything working for the most part as it is
monitoring my house bank and can pick up the drains of all the electrical stuff
and the change from solar. What I am wondering is how to get it to se the
alternator.

3. My setup is as follows. I have the battery switch that has bank 1 and 2 all and
off. On bank on 1 have two batteries one is 85ah and 140ah connected together.
Bank 2 is the starting battery.

The bmr picks up everything from bank 1 just fine. I can but haven't wired it to
bank 2 yet.

4. My question is where will the alternator put it's charge? Does it
just put it back into the starting battery or is it wired to the electrical
panel so it will change all banks? Do I have to change the dale to all to charge
all battery's from the alternator?
1. The OEM alternator was 55A.
2. Seeing the alternator: most battery monitors measure NET charge. That means that if your fridge is on drawing 5A and your alternator is producing 20A, the monitor will see 15A. Same thing with your solar panel. If you want to see what the alternator is producing, turn everything else off, including the solar.
3. Don't understand "connecting to Bank 2, yet" bu I do not know what your monitor is capable of doing. If it does two banks for monitoring amp hours, that's great. Many monitors measure the house bank amp hours but only voltage from a second bank. Depends on what you have. I know I could look it up, but it's your monitor, right?
4. It all depends on how it's wired. Most OEM arrangements have the AO (alternator output) going through the C post of the 1-2-B switch. Here's some information that might interest you:

Basic Battery Wiring Diagrams This is a very good basic primer for boat system wiring: Basic Battery Wiring Diagrams

This is another very good basic primer for boat system wiring: The 1-2-B Switch by Maine Sail (brings together a lot of what this subject is all about)
1/BOTH/2/OFF Switches Thoughts & Musings - SailboatOwners.com

Alternator/Batteries & "The Basic" 1-2-B Switch BEST Wiring Diagrams

You migth also be interested in this: http://www.sailnet.com/forums/diesel...formation.html

Stu Jackson, C34, 1986, M25 engine, Rocna 10 (22#)

Last edited by Stu Jackson; 05-14-2013 at 03:07 PM.
Stu Jackson is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
A4 alternator? seaspot Atomic 4 31 04-01-2013 04:27 PM
Wiring alternator/regulator questions dodgydingo Electrical Systems 6 08-19-2011 07:03 PM
2nd Alternator cacique1977 Gear & Maintenance 9 01-17-2011 07:40 PM
Will any alternator do? hertfordnc Gear & Maintenance 10 11-05-2007 11:19 PM
Bad alternator??? cgha33 Gear & Maintenance 11 10-12-2006 04:56 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome