ammeter vs. volt meter

Yup, volts are a good crutch for those that don't t really understand a charging system.

Beware.. A low resolution tractor voltmeter, especially an un dampened one can read from 10-15 volts and you may not know exactly what you got bouncing thru a field.

10v and your bat is dead, might run the coil, but you will be stranded, and it wont restart.

Or, lets say you loose a cell or 3.. Alt will keep her running, show 13-16 on the meter, and she will be deader than a doornail when you turn her off.

A center 0 net reading ammeter on the other hand tells you the condition of your battery and charging system.

Negative deflection, you are discharging, positive deflection, you are charging.

Larger than normal positive deflection for much longer than normal, and you may have a cell going bad.

Your volt meter will show 12v on a very very weak battery.. One that drops to 4v and clicks the solenoid when you hit the start button.

Voltmeters just don't really tell you anything super useful, without having a center 0 ammeter to fill in all the data you actually need. both would be great, but if only one, I'd take an ammeter any day... But you'd have to know how to interpret all the data it is showing you.
 

Put a voltmeter in dat hole life will be good... If you have a issue voltage is the first thang you need to know, some just don't get it and I spec never will....
 
You can put either on your tractor. I was going to put a volt meter on mine but got to thinking which is more helpful to me. An amp meter strictly tells you how many amps your using after you start your tractor. most of those amps are going back in to your battery to charge it up that why after you start your tractor it might show 6/7 amps on a good battery then drops back down to what your actually using which is probably 2/3 amps and your battery is back fully charged. Its a good indicator that your battery is getting weak as after while those 6/7 amps becomes 12/14 amps then drops down to 2/3 would indicate your charging system is working fine but it takes a little longer to charge your battery. choice is strickly up to the owner preference. mine is an amp.
 
You can have both ammeter and volt meter if you want to. Every new Kenworth I bought I specfied both ammeter and volt meter in them.
 
"...It's yer tractor and you can do ennythang you want to it, except paint it yeller and green..." That was an old Dell-ism. If'N it were my tractor, and I did a 12V conversion, first it would be done correctly and secondly, I'd keep the AMMETER. VOLTMETERS can be all over and not tell you if actually charging the battery -with AMPERES. Having both would be OK, but only room for one or the other unless you wanna cut another hole somewhere. So, yes, it does matter. SEE SOUNDGUY's reply below.

TPD
 
Compare current through a wire to water through a hose. Voltage = pressure, current (amps) = rate of flow
 
Thanks for the info, soundguy. You're right. Ammeters aren't very useful if you don't understand what they're telling you (sorta like Chinese, but easier to learn). Since we only have 2 1/2 acres, I'm not too worried about getting stranded. I'll never be over a hundred yards from the house! My wife could carry a battery that far!
 
I hear ya. In non critical situations, you could even have an idiot light.

To really make use of the ammeter, you need a bit of electronics background. That's not for everyone, and that's understandable.

A multi gage with amps, volts and a warning light/buzzer would be the cats meow, but just not warranted on the average machine.

Have a great one.

( sounds like ya got a strong wife, mines getting a bit long in the tooth to lift heavy stuff, but I'm sure she'd drive out into the pasture for a booster cable service call :) )
 

i have several VOMs (two of which are analog) to read volts with, should i need it. i have zero ways to read DC amps > ~ 500 milliamps if i remove the ammeter from the tractor.

i'd be an even bigger fool than i already am to disable the one and only thing i have that will show me amperage in my tractor.
 
Since we only have 2 1/2 acres, I'm not too worried about getting stranded. I'll never be over a hundred yards from the house!


It is really not a big deal either way . The biggest electrical issue you will probably have is forgetting to turn the key off if you do reasonable maintenance and daily inspections before use . An idiot light or LED volt meter would help remind you that the key is still on . You will probably sense that it is difficult to start before noticing a needle on a gauge . If I had to choose only one it would be a hand held meter that I could use on other projects . I used the hole for a temp gauge which fits my needs better .
 

I prefer an idiot light myself.
I run all 65 and newer Fords and they have fuel and temp gages but not for volts or oil pressure. Just idiot lights.
That big red eye will get your attention much quicker than a needle on a gage will.
 

Voltmeters just don't really tell you anything super useful...

To really make use of the ammeter, you need a bit of electronics background...

Good thang sounder has a good paying day job he would never make it repairing motorized equipment with out a voltmeter and understanding how to apply it...

What a crock of B.S.
 
(quoted from post at 12:52:12 08/04/18) Hogwash,

Volts are what matters, amps are just there to create the voltage.
Volts are nothing but potential, like a water tower, amps is like water flowing thru the pipes. nothing is done without the flow of amps.
 
I use a voltmeter daily in my good paying engineering job.

My comment, in context was specifically as stated about a low resolution, undampened voltmeter with a twitch needle on a vibrating tractor in a bumpy field.

In that situation, a voltmeter isn't real use full if you cat tell I it is reading 10v or 15v.

I make a good living operating hundreds of thousands of dollars worth of electronic equipment that sees daily use for 16+ hours a day. I'm also the person that maintains and troubleshoots and repairs that equipment.

A voltage reading is a small piece of a big puzzle.

Lets face it, you can see 14v on a meter and have a dead battery, or a contact that wont pass anything over microamps.

How long have you had your engineering degree?
 
I have had my engineering degree for 35 years.

Having both an ammeter and a voltmeter is ideal, but in reality an idiot light is probably most useful.
 
My reply was to Hobo, however, agreed that an idiot lamp at least denotes discharge.
I'd take an idiot lamp over a straight voltmeter.

In an battery/alternator charge system, you can have a non charging battery with dead cells as a small load plus the rest of the electrical system load, and your alternator and its vreg will keep voltage on target, turn the key off and poof, you are stranded with a dead battery.

Voltmeter helped 0%, all it tells you I your alt was working when you turned the key off.

Told you 0 about the battery or any discharge condition.
 
E=IR

They are all related.

Understanding the relationship, and deciding what your meter can tell you and is telling you makes the difference.
 

[b:1ac3666fe3]"Hogwash,

Volts are what matters, amps are just there to create the voltage."[/b:1ac3666fe3]

if that were true, u could use 5 AAA batteries to start your 6 volt tractor, right?

i'm even supplying 7.5 volts. that has to be an upgrade.
 

Not the same place you got yours thank god... You are off base real bad no need to make excesses for it that satisfy only you,,, your bouncing meter is not a good'N BTW and none of the other excuses either....

You KNOW a voltmeter is the first piece of equipment needed to diagnosis an automotive electrical system its the fist piece of the puzzle you are letting your degree get the best of you...

We got You Got A Degree out of the way I think that's were you were headed to start off with... Life would be much easier if you and others learn how to apply voltage to your everyday use of your tractor...
 
Alabama Jim, I think you kinda answered your own question.... Use what you prefer and can relate to...

Pay no mind to the *A TEAM* members arguing about their wisdom... they support their own preferences in their arguments... The A Teamers go on as if they were the last bastions of wisdom in a stupid world. Gets Tiresome, I tell ya! :) :)
 
Make mine an ammeter every time. It's good to have both but if I could only pick one it's an ammeter. As has been mentioned already you can derive a lot more useful information about your charging system from an ammeter.
 
Does it matter after changing to 12v? I personally would rather have a volt meter if it doesn't matter.

Detroit moved away from ammeters due to the potential fire hazard they posed behind the dash and the general public's inability to interpret ammeter readings. Volt meters are safer and carry less liability.

My personal choice would be an ammeter because it tells you immediately when you're charging system is acting up - With the large amp hour capacity of modern batteries, there will be a delay in registering a problem with a volt meter.

To answer your question... It obviously it matters to some. Now, let's talk about converting to electronic ignition :D :D :D
 

Dream on are better said more made up stuff...

Amp meter lubbes must have one eye pinned on that meter all the time and fretted your tractor is gonna take a dump...

Manage the volts life will be good... Remember a volt meter is your first tool to diagnosis an issue even with the engine not running try that with you beloved amp meter...

You all know No starts No crank issues are the #1 question asked here is knowing what the amp meter reading is the first step if so I never see it asked.... Some are going to say YES but the problem is the amp meter is a middle of the road gauge, its high end range is not high enoufh and the low end not low enoufh. Its condensed even amp meter lubbers have to rattle that around in there head. Amp meter lubbes sure come up with some neat chit that means nuttin to resolve the issue... If it did you are still gonna go searching for it and more than likely start searching for your voltmeter...

Knowing the voltage on a loaded circuit is hard to beat and Y'all know that I just don't understand why Y'all want to fight it with some of the ridiculous statements that's dreamed up.... All this taking apart and cleaning up can be diagnosed with a volt meter FAST why make it so dang hard...I can tell you why your beloved amp meter offered no information for a successful hunt if you did not catch it your arse is in a jam.... But NO the recommendation is to start taking chit apart till you get lucky... Do you have to have a degree for that type of diagnostic is so its a worthless piece of paper you got hang'N on your wall I hope it was BOGO day the day they issued it to ya...

The #1 Tool recommended to buy is guess what A VOLTMETER whoda thunk it !!! Why do you need one your tractor came with a amp meter put it to work...

Both meters compliment each other your dash mounted amp meter alone is not by itself a good all round way to verify all systems are on go... If I need an amp meter reading you can bet your sweet arse I am not gonna depend on what that cheap arse dash mounted gauge reads...

Hang a voltmeter in dat hole on a 12V system life will be good and much easier to build a battle plan to resolve your issue...
 
Why either? If it makes your tongue tingle, there are volts. If the wire gets hot there is current. If a screwdriver across it makes an arc, you have both. What else do you need?
:twisted:
 
A whole lot of stuff

I hesitate to weigh in but I will :roll:

I am only 67 years old but the industry progression seems to be as follows:[list:449b74aedc][*:449b74aedc]In the beginning machines had a dash mounted ammeter or possibly nothing[*:449b74aedc]Then the ammeter gave way to a voltmeter[*:449b74aedc]The voltmeter gave way to a (dis)charging (idiot) light[*:449b74aedc]My current vehicles have a computerized monitor that sounds an alarm and illuminates a BATTERY icon on the dash when, for what ever reason, the charging system quits working. [/list:u:449b74aedc]Without fail that chime and bright light gets my attention. It doesn't tell me what is wrong but it does tell me I am running on the battery and I better take action IMMEDIATELY else I will be walking home. In my mind that is what all of these systems were meant to do - warn you of a fault not diagnose the fault for you. When I hear that alarm and that battery icon illuminates I head for the shop where I have a variety of diagnostic devices - most notably a voltmeter - for finding the culprit. Other than locating parasitic draws I have never needed or wanted an ammeter for automotive diagnostics. As far as my tractors go a warning light is all I need or want. If I were not so lazy I'd put one on the N's and replace the ammeter with a temperature gauge :twisted:

TOH
 

I don't doubt there ability are there education BUT they are stuck in 50's technology... If they would get over there big head they will discover the power in voltmeter diagnostics that has evolved long after they hung that piece of paper on the wall...
 

If you call me out for a no crank condition you can bet I will throw my Voltmeter on the tow truck seat... You can bet I will hook it up before I touch anything...

If you drive up with a complaint I have to jump it off you can bet the first thing I do is hook a voltmeter on the battery before you cut the engine off...

If its a cranks no start complaint you can bet I want to know what the voltage is under that condition static and dynamic...

It may not fix it but the first information I need to know to take the correct road as I progress...

Amp meters are keep in safe storage mainly to check amp draw are the ability to prove maximum rated amperage output... Other than that they are just eye candy...
 
(quoted from post at 10:40:47 08/05/18)
If you call me out for a no crank condition you can bet I will throw my Voltmeter on the tow truck seat... You can bet I will hook it up before I touch anything...

If you drive up with a complaint I have to jump it off you can bet the first thing I do is hook a voltmeter on the battery before you cut the engine off...

If its a cranks no start complaint you can bet I want to know what the voltage is under that condition static and dynamic...

It may not fix it but the first information I need to know to take the correct road as I progress...

Amp meters are keep in safe storage mainly to check amp draw are the ability to prove maximum rated amperage output... Other than that they are just eye candy...

A good voltmeter in your toolbox is a great tool and I have a good analog one, that said I still like the amp meter on my 8ns.
 
(quoted from post at 18:29:37 08/04/18)
You don't understand it either are don't want to...

I understand the difference between voltage and current just fine. In an ideal world I'd have a voltmeter and an ammeter on my tractor, if I could only choose one it would be an ammeter. If you'd rather have a voltmeter then have at it.
 
I went ahead and got the ammeter because for me it doesn't make any difference. 2 1/2 acres. short walk if it quits. VERY short! Plus it was 8 bucks cheaper! lol
 

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