Itís official, Iím an idiotÖ help! - SailNet Community
Reply
 
LinkBack Thread Tools
post #1 of 33 Old 06-07-2008 Thread Starter
Member
 
lbdavis's Avatar
 
Join Date: Apr 2007
Location: Portland, ME
Posts: 560
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 9
 
Itís official, Iím an idiotÖ help!

Hereís how I proved it:

The electrical system on my boat is rather simple. I have one wet cell house battery and one dedicated wet cell start battery. My only means of charging them are with my alternator (Iím on a mooring.) I have no Link20 or the like; I use my digital voltmeter to take readings in different places in the system and I also read the voltage with my chartplotter.

When charging, I use my make-then-break battery selector switch to change the charging from the starting battery to the house battery to adequately charge both.

Well, today (here comes the idiot part), I accidentally switched the battery selector to switch to (you guessed it) off. It was on ďoffĒ for about .25 seconds before I switched it back to ď1Ē. I screamed many words not suitable for this board and scrambled up to the chartplotter to see if I had indeed fried my alternatorÖ. ď12.3VĒ, says the chartplotter. More bad words from me are followed by bad smells from the engine compartment.

I shut down the engine and feel the alternator. Itís REALLY hot. I calm down and enjoy a wonderful day of sailing on Casco Bay before I fire the engine back up hours later. Each battery was at 12.2V when I started the engine. My typical voltage reading from my alternator would be 14.6V, now it is 13.6V. Apparently I didnít totally fry it, but it certainly isnít charging at full strength.

How could this be? Is it possible to partially fry an alternator? Is this alternator doomed?

I think I'll be getting a new one anyway as I really should have two onboard. Can I keep this one as my backup?
lbdavis is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 33 Old 06-07-2008
Handsome devil
 
Stillraining's Avatar
 
Join Date: Jan 2008
Location: LaConner,Washington
Posts: 3,477
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 10
     
Ibdavis:

Most all modern day alternators are internally regulated...so no you did not fry it but your reg..took a hit of possibly a 100V spike depending on your RPM at the time...13.6 however will still charge your batteries just not quite as efficiently...Sail/run it like it is for awhile you might have gotten lucky..

But it's definitely an easy rebuild if needed...40.00 bucks at an auto electric shop..

Iv done worse and I ain't tellin...

FWIW....14.6 is a little high...13.5 to 14.2 is normal

Last edited by Stillraining; 06-07-2008 at 08:36 PM.
Stillraining is offline  
Quote Quick Reply Share with Facebook
post #3 of 33 Old 06-07-2008
Telstar 28
 
sailingdog's Avatar
 
Join Date: Mar 2006
Location: New England
Posts: 43,290
Thanks: 0
Thanked 14 Times in 12 Posts
Rep Power: 14
         
14.6 might be normal for bulk charging phase with fairly low batteries.
Quote:
Originally Posted by Stillraining View Post
Ibdavis:

Most all modern day alternators are internally regulated...so no you did not fry it but your reg..took a hit of possibly a 100V spike depending on your RPM at the time...13.6 however will still charge your batteries just not quite as efficiently...Sail/run it like it is for awhile you might have gotten lucky..

But it's definitely an easy rebuild if needed...40.00 bucks at an auto electric shop..

Iv done worse and I ain't tellin...

FWIW....14.6 is a little high...13.5 to 14.2 is normal

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.

óCpt. 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.
.

StillóDON'T READ THAT POST AGAIN.
sailingdog is offline  
Quote Quick Reply Share with Facebook
post #4 of 33 Old 06-07-2008
Senior Member
 
trantor12020's Avatar
 
Join Date: Mar 2006
Location: Singapore
Posts: 699
Thanks: 4
Thanked 10 Times in 10 Posts
Rep Power: 10
 
Will a Zap-Stopper prevents this problem of high voltage spike? I understand Zap-Stopper is a zener diode. So I make myself one using 3-4 pcs of 24V 5W zener in parallel and connects it to the alternator output. I imagine a 100V spike would be shunted by the zener when the voltage raises to pass 24V and should there be any reverse voltage from say an induced lightning, that will also be shunted (forward bias) immediately. I haven't any proof this works but in theory.

ps: ibdavis, welcome to "I'm an idiot Club". I'm member too. Recently I drove my boat over a submerged breakwater and broke the rudder mount. I thought I saw the rocks, but somehow the grey matters the holds that piece of info decides to quit at that very moment !

Ken
2002 Hunter 326, SV Millennium 2
1999 Macgregor 26X, SV Millennium

Last edited by trantor12020; 06-07-2008 at 09:59 PM.
trantor12020 is offline  
Quote Quick Reply Share with Facebook
post #5 of 33 Old 06-07-2008
Sea Slacker
 
Join Date: Jan 2007
Posts: 1,789
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 9
 
I am sure more of us are members of this club. We should start a formal membership list, dues, badges and all.

I started my engine with a closed raw water intake seacock and ran it that way for at least a 2-3 minutes. Since it's fresh-water (coolant rather) cooled, it did not overheat (yet) but the exhaust elbow was pretty darn warm to touch and I was afraid that I killed the impeller (though once i opened the seacock and restarted the engine, I got the water flowing so impeller should be fine - I didn't really open it to check, this may be dumb thing number 2 in the making).

I did more dumb stuff, this is just the most recent example.
brak is offline  
Quote Quick Reply Share with Facebook
post #6 of 33 Old 06-07-2008
Senior Member
 
BarryL's Avatar
 
Join Date: Aug 2003
Location: Long Island, NY
Posts: 1,773
Thanks: 3
Thanked 43 Times in 38 Posts
Rep Power: 12
 
regulator

Hello,

When my alternator stopped charging I took it off the boat (took about 10 minutes) and brought it to an automotive electrical repair place. They diagnosed a bad voltage regulator and installed a new one for $40.

I do have a question for you, why don't you just place the switch on 'both' before you start the engine? Then you never need to touch the switch while the engine is running.

Barry

Barry Lenoble
Deep Blue C, 2002 C&C 110
Mt. Sinai, NY

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
BarryL is offline  
Quote Quick Reply Share with Facebook
post #7 of 33 Old 06-07-2008
Senior Member
 
Maine Sail's Avatar
 
Join Date: Jan 2003
Location: Maine Coast
Posts: 5,789
Thanks: 18
Thanked 204 Times in 154 Posts
Rep Power: 16
       
Lb..

There is a really "crafty" alternator guy down behind Paul G. White Tile & Flooring off Allen Avenue. Go down the drive way to the right of Paul G. White and he will be on the right in an old garage. He can fix it!!


P.S. Get one of these and you'll never need to worry about doing that again!!
Battery Link Automatic Charging Relay
It would have already paid for its self!!



Kaza Auto Electric
64 Allen Ave
Portland, ME 04103

(207) 797-6658





______
-Maine Sail / CS-36T


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




© Images In Posts Property of Compass Marine Inc.



Last edited by Maine Sail; 06-07-2008 at 11:31 PM.
Maine Sail is offline  
Quote Quick Reply Share with Facebook
post #8 of 33 Old 06-07-2008
Back to just the Jon boat
 
therapy23's Avatar
 
Join Date: Jul 2007
Posts: 920
Thanks: 4
Thanked 5 Times in 5 Posts
Rep Power: 8
 
Quote:
Originally Posted by BarryL View Post
Hello,



I do have a question for you, why don't you just place the switch on 'both' before you start the engine? Then you never need to touch the switch while the engine is running.

Barry
If this is done without a regulator splitting (controlling) the charge to each, one battery will be overcharged while the other is undercharged.
Common mistake with simple two battery setups with one start and one house. Different discharge states requiring different charge parameters.
therapy23 is offline  
Quote Quick Reply Share with Facebook
post #9 of 33 Old 06-08-2008
Senior Member
 
Omatako's Avatar
 
Join Date: Sep 2003
Location: Auckland New Zealand
Posts: 2,517
Thanks: 1
Thanked 32 Times in 29 Posts
Rep Power: 12
 
Quote:
Originally Posted by therapy23 View Post
If this is done without a regulator splitting (controlling) the charge to each, one battery will be overcharged while the other is undercharged.
Common mistake with simple two battery setups with one start and one house. Different discharge states requiring different charge parameters.
In my experience it's more a case of the voltage regulator seeing the voltage of a fuller battery and then backing off the charge rate so that the flatter battery never gets the chance to charge.

I'm not sure that any battery would over-charge while the other is under-charged.

Andre
Omatako is offline  
Quote Quick Reply Share with Facebook
post #10 of 33 Old 06-08-2008
Senior Member
 
artbyjody's Avatar
 
Join Date: Jan 2008
Location: Bellingham, PNW
Posts: 3,146
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 11
       
Quote:
Originally Posted by Omatako View Post
In my experience it's more a case of the voltage regulator seeing the voltage of a fuller battery and then backing off the charge rate so that the flatter battery never gets the chance to charge.

I'm not sure that any battery would over-charge while the other is under-charged.

Andre
I'll second having a newer battery selector switch. I have revamped my entire electrical system on the Barberis, with new panels as well as the new BlueSea Battery Automatic switching system:



I am very pleased with this over the Perko / Guest standard Off/ 1 / 2 / both switch. Although, I will state that when first installed for some reason it didn't register the actual battery charge of 13.5 for either of the two banks of batteries until after the engine had been run. Not sure why but - its working now.

What I like about it - is its on / off and automatically switches to house batteries if starter battery is low. No interaction is required and it automatically switches charging current to least charged. What this means if you still wire it using a charger where you have one lead to on and another to the other, if one is already to level - the other lead gets diverted to other battery - decreasing battery re-charge times. Or you can go with a single lead from a charger and it saves you from having to buy a more complicated charger.

Thats been my experience with the BlueSea item I provided pic for... and so far - its working as advertised.

related link: Add a Battery - Blue Sea Systems

-- Jody

S/V "
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
" -
1983, Barberis Show 38! or
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.



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







artbyjody is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

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
It''s official cmendoza Cruising & Liveaboard Forum 0 01-12-2006 12:50 PM
Official Address While Cruising ABullard Cruising & Liveaboard Forum 2 08-07-2002 08:42 AM
Checking in with Carl Schumacher SailNet Racing Articles 0 02-28-2001 07:00 PM

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