Repowering Help - Page 3 - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > On Board > Gear & Maintenance
 Not a Member? 


Like Tree2Likes
Reply
 
LinkBack Thread Tools
  #21  
Old 10-04-2011
dasvt's Avatar
Junior Member
 
Join Date: Sep 2011
Posts: 3
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
dasvt is on a distinguished road
take a look at this paper
http://www.exide.com/Media/files/Dow...s%20Manual.pdf

a battery can output lower current for a long period of time the way to make this work is to have a large number of cell and a high voltage with a low draw

i know this will sould like a lot of batteries but I want to start with a 240 volt dc bus
this will take 20 batteries. starting out with 280 volts and drawing down to 200 volts if the current is low I can draw 5-7 amps with an average of 240 volts for 24 hours this is about 2hp average over that time. the drive I am using needs 175 volts dc min so I can draw the batteries down lower, a newer drive is in the design phase and will allow even lower voltages to be used. This is an experiment keep in mind I just want to invest some time and capitol into this as I don't like any of the current system I have read about.

the motor is 20 Hp 3 phase AC 200 volt so It will give me all the power my atomic 6 had and more, of course at high power the battery life goes down faster. I don' know what the results will be but it is worth the effort to find out. I am looking for a nice quiet gen set to add to this , and a wind turbine and also some solar panels. I any one want to come for a look while we do this. you are woelcome to come see as we move along with the project. I am looking for all your good ideas.
Reply With Quote Share with Facebook
  #22  
Old 10-04-2011
kd3pc's Avatar
Senior Member
 
Join Date: Oct 2006
Location: Callao, VA
Posts: 1,311
Thanks: 0
Thanked 8 Times in 8 Posts
Rep Power: 8
kd3pc is on a distinguished road
Please keep us posted, I am not sure your budget and plan are doable with that technology, but we shall see...

Please be careful as DC voltage can be very unforgiving at those levels...and the components often fail in spectacular ways.
Reply With Quote Share with Facebook
  #23  
Old 10-04-2011
tommays's Avatar
Senior Member
 
Join Date: Sep 2008
Posts: 4,219
Thanks: 1
Thanked 24 Times in 24 Posts
Rep Power: 6
tommays will become famous soon enough
20 Hp 3 phase AC 200

What is the frame size and rated 20 HP RPM on this motor ?
__________________
1970 Cal 29 Sea Fever

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

1981 J24 Tangent 2930
Tommays
Northport NY


If a dirty bottom slows you down what do you think it does to your boat
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
  #24  
Old 10-04-2011
mitiempo's Avatar
Senior Member
 
Join Date: Sep 2008
Location: Victoria B.C. Canada
Posts: 6,981
Thanks: 0
Thanked 61 Times in 52 Posts
Rep Power: 7
mitiempo will become famous soon enough mitiempo will become famous soon enough
A 12 volt battery is fully charged at about 12.8 volts resting. The lowest you want to take them to for long life is 50%, or about 12 to 12.1 volts. They are considered dead at 10.5 volts.

As you will have 20 batteries take your lower voltage of 200 and divide by 20. That equals 10 volts and you will never get there running a motor. 50% SOC for your massive bank is about 240 - if you go much lower the batteries will have a very short life.
junkrig likes this.
__________________
Brian
Living aboard in Victoria Harbour
Reply With Quote Share with Facebook
  #25  
Old 10-04-2011
junkrig's Avatar
Both ends are pointy.
 
Join Date: Jun 2011
Location: Missouri
Posts: 228
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 4
junkrig is on a distinguished road
Quote:
Originally Posted by mitiempo View Post
A 12 volt battery is fully charged at about 12.8 volts resting. The lowest you want to take them to for long life is 50%, or about 12 to 12.1 volts. They are considered dead at 10.5 volts.

As you will have 20 batteries take your lower voltage of 200 and divide by 20. That equals 10 volts and you will never get there running a motor. 50% SOC for your massive bank is about 240 - if you go much lower the batteries will have a very short life.
And if you run them all the way down to 10 (200 for the bank) there is no guarantee they will recharge even once.
__________________

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.

S/V Seablossom Nor'Sea 27 with modern junk rig.
Just because I like it.
Reply With Quote Share with Facebook
  #26  
Old 10-04-2011
mitiempo's Avatar
Senior Member
 
Join Date: Sep 2008
Location: Victoria B.C. Canada
Posts: 6,981
Thanks: 0
Thanked 61 Times in 52 Posts
Rep Power: 7
mitiempo will become famous soon enough mitiempo will become famous soon enough
Exactly.
__________________
Brian
Living aboard in Victoria Harbour
Reply With Quote Share with Facebook
  #27  
Old 10-04-2011
kd3pc's Avatar
Senior Member
 
Join Date: Oct 2006
Location: Callao, VA
Posts: 1,311
Thanks: 0
Thanked 8 Times in 8 Posts
Rep Power: 8
kd3pc is on a distinguished road
Quote:
Originally Posted by junkrig View Post
And if you run them all the way down to 10 (200 for the bank) there is no guarantee they will recharge even once.
thus my comment about a spectacular failure of a component...

and without proper fusing or current limiting hardware, the "motor" may spin once or twice and then the batteries may flash/incinerate/smolder...that current has to go somewhere.

And if there is a weak/marginal cell or poor manufacture...well about the same result.

the exide paper is just their spin sheet....nothing new there.

the bigger question is how are you going to convert all this DC to 3phase 200 VAC that the motor you mention requires...or did I miss something there..?
Reply With Quote Share with Facebook
  #28  
Old 10-04-2011
tommays's Avatar
Senior Member
 
Join Date: Sep 2008
Posts: 4,219
Thanks: 1
Thanked 24 Times in 24 Posts
Rep Power: 6
tommays will become famous soon enough
Well

The DC to AC deal would happen in the control and is how its done in the most modern forktrucks

A big issue on a motor that size is it will need a powered cooling fan which will eat some amps

Even a AC VFD drive goes AC to DC back to AC to perform its tricks
__________________
1970 Cal 29 Sea Fever

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

1981 J24 Tangent 2930
Tommays
Northport NY


If a dirty bottom slows you down what do you think it does to your boat
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
  #29  
Old 11-10-2011
dasvt's Avatar
Junior Member
 
Join Date: Sep 2011
Posts: 3
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
dasvt is on a distinguished road
boat is in the building we rented in newport parts are on order i will keep you posted as we make progress
Reply With Quote Share with Facebook
  #30  
Old 11-10-2011
Senior Member
 
Join Date: Oct 2011
Location: Victoria b.c.
Posts: 1,463
Thanks: 2
Thanked 15 Times in 15 Posts
Rep Power: 3
Capt Len is on a distinguished road
Regardless of who you are dealing with, a Kubota has got to be the best bang for the buck
mitiempo likes this.
Reply With Quote Share with Facebook
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
which engine for repowering? prussell Diesel 8 02-01-2014 04:19 PM
Bristol 41 Repowering teshannon Bristol 2 01-04-2007 10:26 AM
repowering vineyardguy General Discussion (sailing related) 16 11-08-2006 08:33 AM
repowering, where to start? ericamadio Gear & Maintenance 0 09-27-2004 06:53 PM
Repowering oz_hole Gear & Maintenance 0 06-05-2003 11:33 AM


All times are GMT -4. The time now is 12:44 AM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012