Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 17-05-2016, 21:32   #1
Registered User
 
Capt.Don's Avatar

Join Date: Aug 2010
Location: Altadena, CA
Boat: Tartan 3500
Posts: 611
Images: 1
Alternator charge pulses 50 Amps

Hi - Just noticed a new behavior with our alternator and house batteries. When the house bank is run down 40%-50% and running our Yanmar 3GM 27HP engine, the engine pulses due to the alternator load at 2 second intervals. I notice the alternator putting out 50+ amps for 2 seconds, then pauses for a few seconds, then repeats. This goes on for about an hour before the charging calms down.

My suspicion is the batteries can't take the 50+ amps, so the regulator circuit shuts down. After 2 seconds, the regulator lets 50+ amps to the battery and it shuts down again.

The house is 3 27 AGMs, for 300 amp-hours, about 5 years old. The alternator is 70 amp alternator controlled by Xantrex 3-stage regulator.

This is a new behavior. I don't believe any wiring has changed. The only thing I can think of is the batteries are going bad or there's something wrong with the regulator.

Any thoughts? As usual, I appreciate your advice,
Don
__________________

__________________
Capt.Don is offline   Reply With Quote
Old 17-05-2016, 23:06   #2
Registered User

Join Date: Jun 2013
Location: canada
Posts: 1,699
Re: Alternator charge pulses 50 Amps

my first guess is the alt feeds the engine battery, and you have an have an ACR device to the house bank that is cycling on and off. this is a problem with a large house bank that is discharged.

if this is not the case, then sounds like an alt or regulator issue.

no way it's normal. bad batteries would not cause this.

you need to trace all the alt and battery wiring and figure out how everything works
__________________

__________________
smac999 is offline   Reply With Quote
Old 17-05-2016, 23:21   #3
Registered User
 
Capt.Don's Avatar

Join Date: Aug 2010
Location: Altadena, CA
Boat: Tartan 3500
Posts: 611
Images: 1
Re: Alternator charge pulses 50 Amps

Smac - alternator charges house. No combiner or relay between house and start. The Heart 1000 charger/inverter has an echo charge, but I believe this is only in-use when on shore power. Agree it is not normal. I'll dig into the wiring to see if anything missing or loose. Thanks!
__________________
Capt.Don is offline   Reply With Quote
Old 17-05-2016, 23:25   #4
Registered User

Join Date: Jun 2013
Location: canada
Posts: 1,699
Re: Alternator charge pulses 50 Amps

so how do you charge both batterys from engine? do you manually put a battery switch to 1+2 ?
__________________
smac999 is offline   Reply With Quote
Old 17-05-2016, 23:36   #5
Registered User

Join Date: Mar 2016
Posts: 33
Re: Alternator charge pulses 50 Amps

If you have a way to isolate each of the batteries, you might check to see if one is at an odd voltage. Also feel when they are charging to see if one is warmer than the others.

IMHO, 5 year old batteries are very old, and while AGM batteries last better than regular deep discharge batteries, I would think that any failure might be there. A single bad cell could cause this.

You used to be able to charge the batteries without the pulsing, probably without the 50 amp bursts. They probably had a higher back voltage. But then they finally charge. Huh.

Well, I would still look at the batteries. In the old days, you could check the specific gravity of each cell. Now you have to look at the voltages of each cell. But you can probably only check the total battery voltage.

Check it when fully charged, check out when discharged. Oh yeah, you are remaking something out. Letting it run like that will probably burn out your alternator or worse.
__________________
Brasshopper is offline   Reply With Quote
Old 18-05-2016, 00:44   #6
Registered User

Join Date: Jan 2010
Location: Puget Sound, USA
Boat: Lyman-Morse 54
Posts: 206
Re: Alternator charge pulses 50 Amps

Could the belt be loose? If this happens when the batteries are drained then the alternator is at peak output and maximum load on the belt. You say it settles down after charging for a while, when batteries are not accepting full alternator output and less load on the belt. The belt tension may be right on the edge of tight enough but slipping under max load?
__________________
Pyxis156 is offline   Reply With Quote
Old 18-05-2016, 05:44   #7
Registered User

Join Date: Oct 2010
Location: The boat - New Bern, NC, USA; Us - Kingsport, TN, USA
Boat: 1988 Pacific Seacraft 34
Posts: 421
Re: Alternator charge pulses 50 Amps

Check the connections of the red wire from the regulator to the battery +. I'll bet something is loose or corroded.

I have a similar set-up: Yanmar 3HM35F, 105A CS-130 alternator, Xantrex XAR regulator, 3-group 31 batteries for the house and a group 24 spiral for the engine, Xantrex Echo charge. I have had the issue twice.

Bill Murdoch
1988 PSC 34
Irish Eyes
__________________
wsmurdoch is offline   Reply With Quote
Old 18-05-2016, 05:50   #8
Marine Service Provider
 
Maine Sail's Avatar

Join Date: Jan 2007
Location: Maine
Boat: CS-36T - Cupecoy
Posts: 3,060
Re: Alternator charge pulses 50 Amps

Sounds like a bad regulator neg, reg B+, reg field connection or temp sensor, if installed... If all those check out reg could be bad.

Remove, clean and re-terminate all regulator & battery/alt connections...
__________________
Marine How To Articles
Maine Sail is offline   Reply With Quote
Old 18-05-2016, 07:22   #9
Registered User
 
Capt.Don's Avatar

Join Date: Aug 2010
Location: Altadena, CA
Boat: Tartan 3500
Posts: 611
Images: 1
Re: Alternator charge pulses 50 Amps

Thanks for all the input - I will work through the connections, belt tension, etc. I'll have to run down the house bank to check voltages, heat, etc.

As far as charging the start battery - I have an A/B/Both switch that I could use to charge the start battery. It doesn't take much to start the Yanmar and I've never had to switch over. I like the simplicity of this setup.
__________________
Capt.Don is offline   Reply With Quote
Old 18-05-2016, 11:19   #10
Registered User

Join Date: May 2016
Posts: 8
Re: Alternator charge pulses 50 Amps

Here's a couple of recommendations. You may have a bad regulator from the alternator, but this would be a last resort swapout. Check all your wires to the batteries and the battery bank. Sometimes a corroded connection creates enough of the voltage drop that the alternator thinks the batteries are charged which is why it turns off and then turns back on again after stops producing current because it sees the nominal battery voltage is lower and turned itself back on again. We've also seen a loose alternator belt cause a similar problem.

You may be also right regarding your battery bank. It's possible that one of the batteries has gone bad. That will require a little bit more troubleshooting. Recheck all of your wires as a starting point.
__________________
eMarineSystems is offline   Reply With Quote
Old 18-05-2016, 11:55   #11
Registered User
 
SouthernPride's Avatar

Join Date: Aug 2015
Location: Charleston, SC
Boat: 53' Hatteras Cruising Yacht
Posts: 101
Re: Alternator charge pulses 50 Amps

Either flat spot/coil damage or bad capacitor in the alternator
__________________
SouthernPride is offline   Reply With Quote
Old 18-05-2016, 18:04   #12
Registered User
 
Capt.Don's Avatar

Join Date: Aug 2010
Location: Altadena, CA
Boat: Tartan 3500
Posts: 611
Images: 1
Re: Alternator charge pulses 50 Amps

A quick update - there was some minor corrosion on all the positive ring terminals. I cleaned and reconnected. The alternator belt was a little loose, but I don't think this was the problem. Also tightened. I have to discharge the house bank to retest - hopefully this weekend

Thanks for all the suggestions.
__________________
Capt.Don is offline   Reply With Quote
Old 19-05-2016, 01:53   #13
Registered User
 
nigelmercier's Avatar

Join Date: Jul 2011
Boat: Bavaria 47
Posts: 172
Re: Alternator charge pulses 50 Amps

Quote:
Originally Posted by SouthernPride View Post
Either flat spot/coil damage or bad capacitor in the alternator
Which capacitor would this be?

My Balmar charger has a small engine mode for exactly this reason, it halves the output current when switched. Might be worth checking the Xantrex.
__________________
Nigel
Got a Bavaria? Want a Bavaria Forum? Click here!
nigelmercier is offline   Reply With Quote
Old 19-05-2016, 04:41   #14
Moderator Emeritus
 
GordMay's Avatar

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 31,583
Images: 240
Re: Alternator charge pulses 50 Amps

Greetings and welcome aboard the CF, eMarineSystems.
__________________
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"



GordMay is offline   Reply With Quote
Old 19-05-2016, 05:11   #15
Registered User

Join Date: May 2014
Boat: Morgan Out Island 41
Posts: 702
Images: 2
Re: Alternator charge pulses 50 Amps

Given that the regulator is a Xantrex, and Xantrex is know for producing just crap product quality... Don't rule out that the regulator has died! check the simple (inexpensive) stuff first.
__________________

__________________
pcmm is offline   Reply With Quote
Reply

Tags
alternator

Thread Tools
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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Amps v Amp hours v Amps/Hr StuM Electrical: Batteries, Generators & Solar 255 25-01-2016 15:21
Volvo D130 Tacho pulses ducati996guy Engines and Propulsion Systems 11 25-09-2015 20:06
Anyone seen a stainless exercise bike that would charge batteries at 10-20 amps? Helia 44 Multihull Sailboats 42 04-11-2014 04:30
When to Charge--Volts vs Amps? mestrezat Electrical: Batteries, Generators & Solar 33 15-08-2012 05:21



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 17:21.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.