Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 19-06-2013, 15:41   #1
VVD
Registered User

Join Date: Jun 2010
Location: Sint Maarten / Saint Martin
Boat: Caliber47LRC - MAKAI
Posts: 78
Alternator putting out 100amps at 1400RPM

We just had our alternator serviced. Now it is putting out too many amps while it is supposed to only put out 64AMPS it is throwing more than a 100amps. What could be wrong?
VVD is offline   Reply With Quote
Old 19-06-2013, 15:55   #2
Registered User
 
DumnMad's Avatar

Join Date: Mar 2012
Location: Nelson NZ; boat in Coffs Harbour
Boat: 45ft Ketch
Posts: 1,559
Re: Alternator putting out 100amps at 1400RPM

My new one did something like that. Apparently when both alternators were linked through the batteries the batteries were sending mixed signals to the controller. So if the starter battery was connected only to the small alternator and the house bank only to the big alternator all was OK.
DumnMad is offline   Reply With Quote
Old 19-06-2013, 15:57   #3
CF Adviser
 
Bash's Avatar

Join Date: Dec 2008
Location: sausalito
Boat: 14 meter sloop
Posts: 7,260
Re: Alternator putting out 100amps at 1400RPM

Quote:
Originally Posted by VVD View Post
We just had our alternator serviced.
Serviced? Was it rebuilt?
__________________
cruising is entirely about showing up--in boat shoes.
Bash is offline   Reply With Quote
Old 19-06-2013, 16:02   #4
VVD
Registered User

Join Date: Jun 2010
Location: Sint Maarten / Saint Martin
Boat: Caliber47LRC - MAKAI
Posts: 78
Re: Alternator putting out 100amps at 1400RPM

Yes it was rebuilt
VVD is offline   Reply With Quote
Old 19-06-2013, 17:12   #5
Registered User

Join Date: Dec 2008
Location: Oriental, NC
Boat: Mainship Pilot 34
Posts: 1,461
Re: Alternator putting out 100amps at 1400RPM

If this is an externally regulated alternator, then the wiring from the alternator to the regulator is screwed up and is sending full unregulated field current to the alternator.

If it is an internally regulated alternator then something electrically was screwed up in the rebuilding.

Either way, your alternator will burn up soon if this isn't fixed.

David
djmarchand is offline   Reply With Quote
Old 20-06-2013, 12:21   #6
Eternal Member

Join Date: Jul 2006
Posts: 4,046
Images: 4
Re: Alternator putting out 100amps at 1400RPM

There are several possibilities.

Assuming that your measurements are correct, i.e., your "rebuilt" 60 amp alternator is really putting out 100 amps @ 1,400 engine RPM, then....

1. during the rebuild, either the rotor was rewound with more turns than the original, OR another rotor with more windings was substituted;

2. the alternator is somehow getting full-field current, without regulation;

3. the alternator has an internal regulator which is connected and is not operating properly;

4. the external regulator (MC-612) isn't connected properly or isn't working properly.

These last three are unlikely in and of themselves to explain a jump from 60A output to 100A output, but could be part of the problem -- together with the rotor-with-more-windings possibility.

Bill
btrayfors is offline   Reply With Quote
Old 25-06-2013, 22:16   #7
Registered User

Join Date: Jun 2013
Location: canada
Posts: 4,642
Re: Alternator putting out 100amps at 1400RPM

they probably rewond it better / bigger.

even with full field a 64amp alternator can't put out more then 64 amps... that is a max rating. (which was tested and will only been seen at full field)
smac999 is offline   Reply With Quote
Old 25-06-2013, 22:24   #8
Registered User

Join Date: Mar 2009
Location: North to Seattle
Boat: Cooper 416
Posts: 279
Re: Alternator putting out 100amps at 1400RPM

Quote:
Originally Posted by djmarchand View Post
If this is an externally regulated alternator, then the wiring from the alternator to the regulator is screwed up and is sending full unregulated field current to the alternator.

If it is an internally regulated alternator then something electrically was screwed up in the rebuilding.

Either way, your alternator will burn up soon if this isn't fixed.

David

David has the answer.
Redcoat is offline   Reply With Quote
Reply

Tags
alternator

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not 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 Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Advertise Here


All times are GMT -7. The time now is 22:01.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.