|
Sponsored Links (Register now to hide all advertisements) |
|
|
Thread Tools | Display Modes |
05-28-2014, 06:27 AM | #1 |
Senior Member
Join Date: Mar 2011
Location: North Carolina
Posts: 191
|
What is the normal "behavior" for the ammeter 6volt pos ground
Hey Barners,
Last weekend was huge for getting my car on the road. Tied up a lot of loose ends and got her out on the road putting on some miles! I realized that I am still concerned about the charging system and I also realized that I really had no clue whatsoever what the normal behavior for the ammeter is. I have been worried about getting stuck, so I have been persistently checking the battery voltage at the ignition switch. It has been consistently between 6.2 and 6.4 (napa battery, close to 2 years old) As I was driving last night home from work in her, the ammeter showed discharge most of the time as I was driving with the lights on. Got home and checked voltage and she was as good as when I started, checked voltage again this morning and same. The ammeter needle doesn't really swing over to charge ever. It shows slight discharge when I am running during the daytime, it shows a bit bigger discharge at night. However it seems like the generator is keeping up. Any info would be appreciated! |
05-28-2014, 06:53 AM | #2 |
Senior Member
Join Date: Apr 2011
Location: Hertford (UK)
Posts: 905
|
Re: What is the normal "behavior" for the ammeter 6volt pos ground
Assuming you have a three brush dynamo the charge rate is adjustable. With everything off my Model B charges at 12 amps or thereabouts. With headlights on it shows a discharge of around 2 amps.
Is your ammeter reliable and have you checked it with another piece of equipment? |
Sponsored Links (Register now to hide all advertisements) |
|
05-28-2014, 07:24 AM | #3 |
Senior Member
Join Date: Mar 2011
Location: North Carolina
Posts: 191
|
Re: What is the normal "behavior" for the ammeter 6volt pos ground
Don't have aanother ammeter yet. Gauge isNOS, all new wiring. Generator is two brush type, just got new brushes.
|
05-28-2014, 08:39 AM | #4 |
Senior Member
Join Date: Jun 2010
Location: San Antonio, Texas
Posts: 16,440
|
Re: What is the normal "behavior" for the ammeter 6volt pos ground
Not enough information. We need to know what year a vehicle. Early vehicles have a genuine ampere meter with two terminals on the back but the later cars have an induction type amp meter where the charge wire passes by the back of the unit but is not physically attached.
The two units give different indications so it's hard to relate you what you need to know. |
05-28-2014, 09:00 AM | #5 |
Senior Member
Join Date: Mar 2011
Location: North Carolina
Posts: 191
|
Re: What is the normal "behavior" for the ammeter 6volt pos ground
1946 Business Coupe.It has been a while since I looked at back of ammeter butI believe it just passes by the back and doesn't physically attach.
|
05-28-2014, 09:41 AM | #6 |
Senior Member
Join Date: Mar 2011
Location: Overland Park, Ks
Posts: 559
|
Re: What is the normal "behavior" for the ammeter 6volt pos ground
Sponsored Links (Register now to hide all advertisements)
|
05-28-2014, 11:15 AM | #7 |
Senior Member
Join Date: Oct 2010
Location: Orem, Utah
Posts: 5,762
|
Re: What is the normal "behavior" for the ammeter 6volt pos ground
Here are the specs for the generator for you to check at various RPM's. Sounds like to me that generator isn't charging or isn't charging enough. If recently installed or hooked up after a long time (months or years) the generator may need polarized to get going.
As you can see from the following specs, you should be getting close to 7.2 volts when the generator is charging at fast idle. Check that voltage with fast idle and see. If the voltage at the battery doesn't rise at all from engine off to fast idle your generator is not charging. And, here's a schematic of the whole charging system if that helps understand how it all works. Since that diagram didn't come with a legend for the numbers I'll give it my best shot: 1. Generator battery/armature terminal. 2. Regulator armature terminal 3. Regulator field terminal 4. Generator field terminal 5. Generator ground (no specific connection, just through mounting on engine) 6. Regulator battery terminal 7. Connection to the rest of the car's electrical system 8. Ammeter (Battery gauge) 12. Starter solenoid connection 13. Battery negative post 14. Battery positive post 15. Connection of battery ground strap to firewall 16. Regulator ground terminal 17. Generator ground terminal (grounding directly to regulator)
__________________
Prof. Henry (The Roaming Gnome) "It is good to have an end to journey toward; but it is the journey that matters, in the end.” *Ursula K. Le Guin in The Left Hand of Darkness Last edited by Old Henry; 05-28-2014 at 11:48 AM. |
05-28-2014, 11:22 AM | #8 |
Senior Member
Join Date: Oct 2010
Location: Orem, Utah
Posts: 5,762
|
Re: What is the normal "behavior" for the ammeter 6volt pos ground
Here is a very lengthy but thorough discussion of charging problems that you might check out: https://www.fordbarn.com/forum/showth...nerator&page=2
__________________
Prof. Henry (The Roaming Gnome) "It is good to have an end to journey toward; but it is the journey that matters, in the end.” *Ursula K. Le Guin in The Left Hand of Darkness |
05-28-2014, 12:37 PM | #9 |
Senior Member
Join Date: Jun 2010
Location: San Antonio, Texas
Posts: 16,440
|
Re: What is the normal "behavior" for the ammeter 6volt pos ground
Induction meters only show the amount of current flow at any given time. It may show a charge for a bit imediately after you start the car but will go back to neutral after the battery is up to full charge state. It will show a discharge when the generator is inoperative or not keeping up with the current draw such as at night with lights on and brake lights on with heater fan and other electrical accesories also on.
If you have a volt/ohm meter, you can measure the voltage at the battery with the car running. The voltage regulator will boost the voltage above the 6-volt mark. It may not read exactly 7.2-volts but it should be above 6-volts in most cases. |
05-28-2014, 02:31 PM | #10 |
Member Emeritus
Join Date: May 2010
Location: Madison, NJ
Posts: 5,230
|
Re: What is the normal "behavior" for the ammeter 6volt pos ground
But it does sound like it is not charging...
Quick and dirty verification of generator charging: 1. Slow idle, headlights on, rev up engine to a bit above idle. Headlights should brighten. 2. Pull out throttle knob slightly so engine is running at a pretty brisk idle, remove on battery cable. If engine stops, generator is not working. There is an easy way to "full-field" the regulator briefly, making gen go to full output regardless of what the regulator is doing. This is a worthwhile check because reg failure is much more common than gen. I've posted that on the HAMB because I can never remember it,along with instructions for properly polarizing the Ford system, another quick checkup item. |
05-28-2014, 03:31 PM | #11 |
Junior Member
Join Date: Dec 2010
Location: Whiting, NJ
Posts: 23
|
Re: What is the normal "behavior" for the ammeter 6volt pos ground
I have a 6 volt positive ground alternator in my F-3. The ammeter in this truck is the stock induction type meter. The ammeter shows that the system is charging right after the engine is started then gradually tapers back to the "neutral" position.
|
05-28-2014, 03:46 PM | #12 |
Member Emeritus
Join Date: May 2010
Location: Madison, NJ
Posts: 5,230
|
Re: What is the normal "behavior" for the ammeter 6volt pos ground
...and that is the normal position for an ammeter on a car with the regulated type generator (2 brush Ford) as it will be regulated to the current actually being used.
|
05-28-2014, 09:48 PM | #13 |
Senior Member
Join Date: Mar 2011
Location: North Carolina
Posts: 191
|
Re: What is the normal "behavior" for the ammeter 6volt pos ground
Great info guys , let me do some poking around and get back to you!
|
|
|
Sponsored Links (Register now to hide all advertisements) |
|