Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 18-11-2008, 10:02   #1
Marine Service Provider
 
AnchorageGuy's Avatar

Join Date: Mar 2003
Location: Wherever the boat is!
Boat: Marine Trader 34DC
Posts: 4,618
New Boats Charging System

The new boat has a charging system set up that I am not too sure of. It has a single Iota 45 charger connected to a Hellroaring battery isolator which is connect to two banks of two golf carts and a third start battery. The alternator is also connected to the isolator and charges all three batteries. Is there anything inherently wrong with this set up. I know there are more optimal set ups and will address those later but for now is this OK?
__________________

__________________
Chesapeake Bay, ICW Hampton Roads To Key West, The Gulf Coast, The Bahamas

The Trawler Beach House
Voyages Of Sea Trek
AnchorageGuy is offline   Reply With Quote
Old 18-11-2008, 14:08   #2
Registered User

Join Date: May 2003
Location: East Coast & Other Forums!
Posts: 913
You're fine Chuck. You'll see a little voltage drop but you can keep 'em charged that way. The Iota (with the 3 stage option right?) would be better off direct to your house bank and then an echo charger to your start battery would be more optimal but it can wait a bit.
__________________

__________________
Cam - I am no longer a member here. Look for me on other forums...same name.

camaraderie is offline   Reply With Quote
Old 18-11-2008, 14:27   #3
Marine Service Provider
 
AnchorageGuy's Avatar

Join Date: Mar 2003
Location: Wherever the boat is!
Boat: Marine Trader 34DC
Posts: 4,618
Thanks, Cam, I plan on doing just that later
__________________
Chesapeake Bay, ICW Hampton Roads To Key West, The Gulf Coast, The Bahamas

The Trawler Beach House
Voyages Of Sea Trek
AnchorageGuy is offline   Reply With Quote
Old 18-11-2008, 15:15   #4
Registered User

Join Date: Jan 2005
Location: Seattle area (Bremerton)
Boat: C&C Landfall 39 center cockpit "Anahita"
Posts: 1,076
Images: 6
Get rid of the diode isolator. They are nothing but trouble and prevent the alternator and Iota from properly charging the batteries unless both sources have direct battery sensing. Use battery combiners to do the isolator function or else merely use your manual method of combining with switches.

Keep in mind that those batteries need to get to 14.4V @ 70 deg F in order to recover lost capacity with deep discharge cycling. Diode isolators will prevent that unless the sources have direct battery voltage sensing. Begrudge the diode isolator losses and lack of reliability. Even with direct battery voltage sensing should a diode fail you could damage the alternator if its regulator is an external 3-step one (as it should be).
__________________
"I don't think there'll be a return journey Mr. Frodo". Samwise Gamgee
Rick is offline   Reply With Quote
Old 18-11-2008, 15:43   #5
Marine Service Provider
 
AnchorageGuy's Avatar

Join Date: Mar 2003
Location: Wherever the boat is!
Boat: Marine Trader 34DC
Posts: 4,618
Quote:
Originally Posted by Rick View Post
Get rid of the diode isolator. They are nothing but trouble and prevent the alternator and Iota from properly charging the batteries unless both sources have direct battery sensing. Use battery combiners to do the isolator function or else merely use your manual method of combining with switches.

Keep in mind that those batteries need to get to 14.4V @ 70 deg F in order to recover lost capacity with deep discharge cycling. Diode isolators will prevent that unless the sources have direct battery voltage sensing. Begrudge the diode isolator losses and lack of reliability. Even with direct battery voltage sensing should a diode fail you could damage the alternator if its regulator is an external 3-step one (as it should be).
Rick, This particular isolator is only suppose to have a 0.05 to 0.08 voltage loss. At this point it is what I have and plan to upgrade and improve including adding another Iota 45 and run both chargers with a echo charger for the starting bank. BTW, what battery combiners would you recommend for two banks plus starting battery? But just wanted to be sure I am OK for right now. We just bought the boat and have lots of upgrades and improvements to do. Thanks.
__________________
Chesapeake Bay, ICW Hampton Roads To Key West, The Gulf Coast, The Bahamas

The Trawler Beach House
Voyages Of Sea Trek
AnchorageGuy is offline   Reply With Quote
Old 18-11-2008, 19:24   #6
Moderator Emeritus
 
David M's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: San Francisco Bay
Boat: research vessel
Posts: 10,150
Battery combiners are not perfect nor close to it. Pick your poison.
__________________
David

Life begins where land ends.
David M is offline   Reply With Quote
Old 19-11-2008, 02:38   #7
Moderator Emeritus
 
GordMay's Avatar

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 31,573
Images: 240
Chuck:
Which particular isolator "is only supposed to have a 0.05 to 0.08 voltage loss"?

At rated currents, a silicon diode has a forward voltage drop of about 1.0 VDC, and a Schottky diode drops about 0.6 VDC.
__________________
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 19-11-2008, 07:18   #8
Marine Service Provider
 
AnchorageGuy's Avatar

Join Date: Mar 2003
Location: Wherever the boat is!
Boat: Marine Trader 34DC
Posts: 4,618
Quote:
Originally Posted by GordMay View Post
Chuck:
Which particular isolator "is only supposed to have a 0.05 to 0.08 voltage loss"?

At rated currents, a silicon diode has a forward voltage drop of about 1.0 VDC, and a Schottky diode drops about 0.6 VDC.

Gord, They are this type

Hellroaring Battery Isolator/Combiner BIC-75300
__________________
Chesapeake Bay, ICW Hampton Roads To Key West, The Gulf Coast, The Bahamas

The Trawler Beach House
Voyages Of Sea Trek
AnchorageGuy is offline   Reply With Quote
Old 19-11-2008, 08:53   #9
Moderator Emeritus
 
GordMay's Avatar

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 31,573
Images: 240
Hellroaring specifies their voltage drop at 5 amps.
Is that a realistic charge rate?
__________________
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 19-11-2008, 08:58   #10
Marine Service Provider
 
AnchorageGuy's Avatar

Join Date: Mar 2003
Location: Wherever the boat is!
Boat: Marine Trader 34DC
Posts: 4,618
Gord, Have not talked with them yet to get confirmation of info but would not think the voltage drop would increase as charging voltage increases. The unit apparently will let you charge up to 120 amps.
__________________
Chesapeake Bay, ICW Hampton Roads To Key West, The Gulf Coast, The Bahamas

The Trawler Beach House
Voyages Of Sea Trek
AnchorageGuy is offline   Reply With Quote
Old 21-11-2008, 21:25   #11
Registered User

Join Date: Apr 2008
Boat: Pescott,Whitehaven, 11.7m
Posts: 11
Thunder sky Li Fe Ph batteries

Hello Rick , I am setting up a house bank from 8x 3.2 volt 200 ahr lithium iron phoshate batteries ,= principal 24 volt with DC to DC converter for the 12 volt supply .
In respect to these diodes I will have to have a battery monitoring system which runs in connection to modules across each set of terminals , this cuts the system in the event of a voltage drop in any one cell .
Could this be the same as these diodes you mentioned any info or experience you may have would be appreciated .
These Batteries are from the electric automotive industry i am using them on my Cat as a weight saving exercise . ie 8 x 200ahr bank = ~ 56kg .
They are expensive but effectively dry cell batteries ,
I intend to charge from solar Balmar 70 amp alternator plus wind etc .
regards Lance
__________________
Lance is offline   Reply With Quote
Old 21-11-2008, 22:10   #12
Registered User
 
bill good's Avatar

Join Date: Oct 2006
Location: Brisbane Australia
Boat: sold
Posts: 721
lifepo4

Lance,
Why 24v to 12v? would that not involve more losses?
__________________

__________________
bill good is offline   Reply With Quote
Reply

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
1 alternator charging more than other ? gramos Electrical: Batteries, Generators & Solar 7 27-10-2008 11:37
Charging options captden Electrical: Batteries, Generators & Solar 5 01-07-2008 21:47
optima - HeLP, I'm over charging! fla.sailor Electrical: Batteries, Generators & Solar 7 26-09-2007 19:52
Need help with charging system... 24 volt and 12. Zach Electrical: Batteries, Generators & Solar 2 16-07-2007 11:06
Outboard charging system Ted Beyer Electrical: Batteries, Generators & Solar 2 21-06-2005 18:33



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 17:34.


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.