Shunt for panel ammeter? - 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? 
  #1  
Old 06-07-2011
patrickstickler's Avatar
Rhumbunctious
 
Join Date: Dec 2008
Location: Espoo, Finland
Posts: 150
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 6
patrickstickler is on a distinguished road
Shunt for panel ammeter?

I am rewiring my main house panel:



and the load ammeter ("LOAD AMPS") was not hooked up when I bought the boat.

I assume that it needs a shunt of some sort, to be connected inline in the ground lead to the house battery bank, but can't find any definitive guidance by searching.

Can anyone point me in the right direction? Thanks.
__________________
...
If a man speaks at sea where there is no woman to hear, is he still wrong?
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

-
Cruising the Baltic in 'Merihiisi', a 1979 Westerly Berwick Ketch
Reply With Quote Quick reply to this message Share with Facebook
  #2  
Old 06-07-2011
Senior Member
 
Join Date: May 2008
Location: California
Posts: 180
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 7
J36ZT is on a distinguished road
If the ammeter was never hooked up, I doubt you have the required shunt...but look for it anyway between the battery and negative buss. I'm guessing you'll get your answer from "Westerly" or from Welcome to EmproShunts™.

Sorry, as I'm not an electrical expert in any way (also not connected to either business), this is the best I could come up with.

Skipper, J/36 "Zero Tolerance"
Reply With Quote Quick reply to this message Share with Facebook
  #3  
Old 06-07-2011
JimsCAL's Avatar
Senior Member
 
Join Date: May 2007
Location: Glen Cove, NY
Posts: 2,484
Thanks: 2
Thanked 45 Times in 41 Posts
Rep Power: 8
JimsCAL is on a distinguished road
Some ammeters (especially the lower range ones) have the shunt built in, not separate. I would suspect the 30 amp range of yours would mean it has an internal shunt. External shunts are typically designed to have a 50 or 100 mv voltage drop across them at 100% rated current. If you need one, it will have to match the meter.
Reply With Quote Quick reply to this message Share with Facebook
  #4  
Old 06-07-2011
hellosailor's Avatar
Senior Member
 
Join Date: Apr 2006
Posts: 10,797
Thanks: 2
Thanked 97 Times in 94 Posts
Rep Power: 10
hellosailor has a spectacular aura about hellosailor has a spectacular aura about
I'd vote with Jims, odds are the shunt is built in. But "odds" is still gambling, better to check with the maker. If you can't get any information...you can test it with some caution, i.e. connect a AA cell across the leads. If the meter barely twitches, it is reading amos directly from a built-in shunt. If it is designed to work with a shunt, it should misread the battery's available power (maybe 1600mA) as being a large voltage drop ona shunt, and show a 10A or way higher reading.
Reply With Quote Quick reply to this message Share with Facebook
  #5  
Old 06-09-2011
patrickstickler's Avatar
Rhumbunctious
 
Join Date: Dec 2008
Location: Espoo, Finland
Posts: 150
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 6
patrickstickler is on a distinguished road
OK, I dug around in the box of misc. parts and bits that came with the boat and found what appears to be the shunt:





Per my understanding, this is then connected inline in the ground connection from the panel to the battery, and the meter is connected across the shunt, one lead to each side. I.e.


Code:
  
BATTERY NEG ----- SHUNT ----- PANEL GROUND BUS
              |           |
              --- METER ---
Right?
__________________
...
If a man speaks at sea where there is no woman to hear, is he still wrong?
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

-
Cruising the Baltic in 'Merihiisi', a 1979 Westerly Berwick Ketch
Reply With Quote Quick reply to this message Share with Facebook
  #6  
Old 06-09-2011
patrickstickler's Avatar
Rhumbunctious
 
Join Date: Dec 2008
Location: Espoo, Finland
Posts: 150
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 6
patrickstickler is on a distinguished road
One more question... I have a separate monitor for the house bank, so I'd like to use the panel meters to indicate the condition of the starter battery. That would mean connecting the shunt to the starter battery side of the circuit in some fashion, however obviously it couldn't go inline between the starter battery negative terminal and the engine block as it couldn't handle the current of the starter motor.

There is a negative lead from the engine panel to the starter block that looks to be AWG 10 (2.5mm), so I'm thinking that connecting the shunt inline to that ground wire should indicate load/charging of the starter circuit, right? Or should the shut be inline in the ground wire from the alternator?
__________________
...
If a man speaks at sea where there is no woman to hear, is he still wrong?
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

-
Cruising the Baltic in 'Merihiisi', a 1979 Westerly Berwick Ketch
Reply With Quote Quick reply to this message Share with Facebook
  #7  
Old 06-09-2011
JimsCAL's Avatar
Senior Member
 
Join Date: May 2007
Location: Glen Cove, NY
Posts: 2,484
Thanks: 2
Thanked 45 Times in 41 Posts
Rep Power: 8
JimsCAL is on a distinguished road
That sure looks like the shunt and your connection diagram is correct.

I don't think you can use this meter to measure the current when starting the engine. It will be far more than 30 amps.
Reply With Quote Quick reply to this message Share with Facebook
  #8  
Old 06-09-2011
Argyle38's Avatar
Senior Member
 
Join Date: Oct 2010
Location: Connecticut
Posts: 213
Thanks: 10
Thanked 8 Times in 8 Posts
Rep Power: 5
Argyle38 is on a distinguished road
JimsCal is right. If this circuit is also your starting circuit, you need to wire in a solenoid rated to the current of your starting motor (and then some).

Wire it in parallel to the shunt with the signal line wired to your starting motor energizing line.

I know Blue Sea systems sells such a solenoid, 500-700 Amps rated, or something like that. I have one. I have an ammeter wired in to the starting battery so I can see how much it's charging, so I use this solenoid setup to avoid starting current from blowing up my shunt. No problems in 3 years since I wired it up.
__________________
S/V Argyle
Downeaster 38 #40

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Quick reply to this message Share with Facebook
  #9  
Old 06-09-2011
Senior Member
 
Join Date: Jan 2009
Location: Deer Harbor, Washington
Posts: 215
Thanks: 0
Thanked 9 Times in 9 Posts
Rep Power: 6
mitchbrown is on a distinguished road
The analog amp guage on my boat is wired to the + side of the batteries then to the + side of the breakers. Also it doesn't use a shunt per sey it uses a heavy guage coil wrapped a few turns around a needle actuater.

Mitch
Reply With Quote Quick reply to this message Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

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:

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

 
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
Kuldging an Ammeter Shunt? hellosailor Electrical Systems 4 01-22-2011 05:07 PM
ammeter wiring kidnapper Electrical Systems 2 11-21-2010 07:52 PM
Ground connections / monitor shunt installation SteveInMD Electrical Systems 4 07-22-2009 09:25 PM
Link Battery Monitor Shunt Installation SteveInMD Electronics 0 07-22-2009 03:42 PM
Ammeter question jaschrumpf Gear & Maintenance 20 08-03-2007 02:46 PM


All times are GMT -4. The time now is 08:55 PM.

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

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.