DC Ammeter wiring - 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 > General Interest > General Discussion (sailing related)
 Not a Member? 


Reply
 
LinkBack Thread Tools
  #1  
Old 01-05-2011
Junior Member
 
Join Date: Aug 2010
Posts: 6
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
thaeni is on a distinguished road
DC Ammeter wiring

I bought an ammeter to monitor ampere usage on my boat. My boat
has a master DC panel with a switch at the top that turns on all equipment
that is supplied by 12volts. Can I just wire the ammeter to the master switch
that enables all the other devices.
Thanks
Reply With Quote Quick reply to this message Share with Facebook
  #2  
Old 01-05-2011
hellosailor's Avatar
Senior Member
 
Join Date: Apr 2006
Posts: 10,871
Thanks: 2
Thanked 101 Times in 98 Posts
Rep Power: 10
hellosailor has a spectacular aura about hellosailor has a spectacular aura about
You CAN install the shunt anyplace you please, but it will just measure the amperage at that point, through that circuit. The normal place to install it is in the battery common negative/ground cable, so it measures all current being drawn through the battery bank.
Reply With Quote Quick reply to this message Share with Facebook
  #3  
Old 01-05-2011
Junior Member
 
Join Date: Aug 2010
Posts: 6
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
thaeni is on a distinguished road
thanks for advice, but where do I connect the positive too.
Reply With Quote Quick reply to this message Share with Facebook
  #4  
Old 01-05-2011
hellosailor's Avatar
Senior Member
 
Join Date: Apr 2006
Posts: 10,871
Thanks: 2
Thanked 101 Times in 98 Posts
Rep Power: 10
hellosailor has a spectacular aura about hellosailor has a spectacular aura about
A typical digital ammeter will have four leads. Plus and minus, tht go to a 12V power connection like any other electronic device. And two lead for the shunt. One goes to either side of the shunt, plus and minus being only relative for those two. If your display shows minus when it should show plus, reverse those two.
Reply With Quote Quick reply to this message Share with Facebook
  #5  
Old 01-05-2011
erps's Avatar
the pointy end is the bow
 
Join Date: Aug 2006
Location: La Conner, Washington
Posts: 6,215
Thanks: 2
Thanked 26 Times in 26 Posts
Rep Power: 10
erps will become famous soon enough erps will become famous soon enough
Hello,

Doesn't the old style analog amp meter go in series on the positive side though?
__________________
Ray
S.V. Nikko
1983 Fraser 41
La Conner, WA


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


Boating for over 25 years, some of them successfully.
Reply With Quote Quick reply to this message Share with Facebook
  #6  
Old 01-05-2011
Omatako's Avatar
Senior Member
 
Join Date: Sep 2003
Location: Auckland New Zealand
Posts: 2,448
Thanks: 0
Thanked 30 Times in 27 Posts
Rep Power: 12
Omatako will become famous soon enough
My understanding of the connection is that the shunt has four connectors, two large and two small. The large connectors go in line (series) with the +v line from the battery bank to the load side (distribution panel in this case). The small connections go to the back of the ammeter.

In the image below the large holes in the ends take the battery feed to the load. That is those marked as "Diameter 8.5", the small ones marked "M5" go to the ammeter.

The negative connections in the system have nothing to do with the shunt or ammeter.
__________________

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

__________________

"Two possibilities exist: Either we are alone in the Universe or we are not. Both are equally terrifying."

Arthur C. Clarke
Reply With Quote Quick reply to this message Share with Facebook
  #7  
Old 01-05-2011
HDChopper's Avatar
Needing Apehanger Helm
 
Join Date: Oct 2010
Location: AZ
Posts: 495
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 5
HDChopper is on a distinguished road
Correct Omatako.
Yes erps , what HelloSailor mentions would ive you te other use of an Ammeter which would be current draw lso hooked up his way would let one see if thay have a negitive draw while everything should be off...or known as exessive draw which is a good thing to know if it's hapening to your system.
__________________
There is no right way to do the wrong thing

Last edited by HDChopper; 01-05-2011 at 06:53 PM.
Reply With Quote Quick reply to this message Share with Facebook
  #8  
Old 01-05-2011
LakeSuperiorGeezer's Avatar
Senior Member
 
Join Date: Oct 2010
Posts: 551
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 5
LakeSuperiorGeezer is on a distinguished road
Normally you want to measure the current going into the battery banks because when the amps taper off, you know the battery banks are charged up. The alternator will be supplying current for both charging the batteries and for electronics, lighting, pumps, whatever and this includes charging the engine battery bank and any engine electronics. There are usually two battery banks, one for the engine and the other for everything else. With the engine running, usually a relay connects everything together so all banks get charged. So, the problem is finding a place where all the current flows together into one cable. If all the negative cables are brought together at one point and the shunt is connected to that point with the other side of the shunt goes to a common ground, usually on the engine since the starter on a diesel uses many hundreds of amps, then all the current is measured for both banks. Otherwise, if you want to have a shunt on the positive side, you have to choose one bank or the other. However, maybe you want to know how many amps are being pulled from the bank that supplies everything but the engine. When the engine is shut down, knowing the amperage draw will tell you how long you can go without recharging if you calculate amp-hours that are being discharged and know how many amp-hours the batteries can supply. In this case you would put the shunt on the positive cable going to that bank of batteries that supplies the buss and alternator relay connection. You could also tell when that bank is nearing full charge because the amps on the charging side of the meter would taper off. A voltmeter could be used for monitoring both banks, maybe with a switch between banks to you can measure resting voltage (no charging or current draw for at least six hours) to determine how charged up each of the battery banks are. However, be aware that a relay that connects all banks together while the engine is running to charge both banks will show the same voltage on both banks. The relay ties both banks together. The resting voltage varies depending how the state of charge for the battery banks. Trying to describe all this is difficult. A picture would be better. Check out of the library, Boatowner's Mechanical and Electrical Manual: How to Maintain, Repair, and Improve Your Boat's Essential Systems by Nigel Calder

Last edited by LakeSuperiorGeezer; 01-06-2011 at 04:04 PM.
Reply With Quote Quick reply to this message Share with Facebook
  #9  
Old 01-06-2011
Junior Member
 
Join Date: Jan 2011
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
Padeen2 is on a distinguished road
I have a clamp-on dc ammeter. Isn't there a similar style permanently installed ammeter that would be much easier to install, as well as move about to give you different readings for different applications?
Reply With Quote Quick reply to this message Share with Facebook
  #10  
Old 01-06-2011
LakeSuperiorGeezer's Avatar
Senior Member
 
Join Date: Oct 2010
Posts: 551
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 5
LakeSuperiorGeezer is on a distinguished road
Old Style Amp Gauge

Quote:
Originally Posted by Padeen2 View Post
I have a clamp-on dc ammeter. Isn't there a similar style permanently installed ammeter that would be much easier to install, as well as move about to give you different readings for different applications?
It depends on what you want the instrumentation to do. The above shunt type amp meters also integrate the amount of current with respect to time so you get a good idea of how much amp-hours you have used and how much is left, how close the battery bank is to being dead. The amp guages in cars sixty years ago showed the amps flowing to and from the battery. These guages were placed on the hot side of the battery and the rest of the car, but did not include cranking amperage. If the generator were not putting out enough amps to charge the battery, the needle would be to the left of zero on the minus side. If to the right, then the generator was staying ahead of demand, and if the needle gradually came down a little above the plus side of zero amps into the battery, then it was assumed the battery was becoming charged and the voltage regulator was cutting back the generator to not overcharge the battery with too high a voltage. Now days if you want this kind of information, you use a voltmeter to directly measure the charging voltage. You can even buy little LED indicators now that plug into the cigarette lighter that show green yellow red lights for different voltages and tell you a little about what is happening, but not sure how well these would work in salt spray.
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
ammeter wiring kidnapper SailNet FAQ 13 11-21-2010 10:27 PM
ammeter wiring kidnapper Electrical Systems 2 11-21-2010 07:52 PM
Ammeter vs. Voltmeter L124C Electrical Systems 26 09-01-2010 02:35 PM
DC Ammeter Question seap27672 Gear & Maintenance 7 07-05-2008 11:03 AM
Ammeter question jaschrumpf Gear & Maintenance 20 08-03-2007 02:46 PM


All times are GMT -4. The time now is 04:16 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.