amperage guage?

[bigneily]

let me throw this one at yah fellas, always had an issue with a draw somewhere. so today reinsured the cruiser along with a fresh battery, while driving around i noticed the amperage gauge is always reading above the half way line in the positives, what does this mean? is it charging, or taking a charge? just trying to narrow things a bit ....thanx..

 

[Pin_Head]

Yes, it means it is charging. It should drop to near zero in the middle.

 

[bigneily]

how long would it, or should it take to be in the middle? i'm not even powering a stereo or cb...

 

[fj404life]

Depends on how drained your battery was to begin with.

 

[BrianSanDiego]

The ammeter reads current (amps) to and from the battery. If the gauge is reading above half way it means that current is flowing into the battery, from the alternator, and charging the battery. If the ammeter is on the lower side of the scale it means that current is flowing out of the battery to whatever loads are on, such as lights, stereo and whatever. Reasons the battery would be discharging are if the engine is off, broken alt belt, defective alternator or wiring, or if you have more loads (lights and junk) on than the alternator can power. (then current would need to flow from the battery, to make up the difference between the alternator output and the load your devices are consuming)

Having the ammeter in the positive is usually good. It means the alternator is working and recharging or topping off the battery. When you start your rig, you use a pretty big chunk of power (electrical term) from the battery, and your ammeter will be in the positive for a while, while the alternator recharges the battery.

If you have some sort of problem and a load on the battery while the engine is off, your ammeter will be in the positive a lot of the time while the alternator tries to play catch-up with the battery's charge.

Hope this helps. And if I've brain-farted and stated anything incorrectly, y'all feel free to correct me. I'm not gonna' proof-read this chit right now.

B.

 

[bigneily]

thanx for the reply brian very helpfull....

 

[BrianSanDiego]

Hey, Glad to help.

B.

 

[amraspalantir]

does it make sense to add a volt meter to supplement the existing ampere meter?
the fj40 we bought has a additional volt meter and i was wondering if this really helps
monitor the electrical system.or should i just take it out and stick with the ampere meter?

thanks and cheers

 

[Pin_Head]

They are both useful. A volt meter will alert you if the voltage is too high, but it won't tell you the things an amp meter will tell you, like if your battery is charged and how fast it is charging/discharging.

 

[BrianSanDiego]

I personally prefer a voltmeter over an ammeter. With the V meter, at a glance you can tell the alternator's voltage output (should be around 14-14.5 volts).

With the engine off a fully charged battery should read around 12.5V I believe. If the alternator can't keep up with the accessories, the volt meter will read somewhere under your desired 14.5 volts. Plus, with a voltmeter you don't have all that current running through your gauge cluster.

So my preference is the voltmeter, although as Pin-Head pointed out, it doesn't tell you the rate that the battery is charging or discharging. Having both would be nice...
B.

 

[KOOTENAY KRUZER]

I have both in my BJ40. I refer to the voltmeter more than the ammeter. For one thing, it shows me what the voltage regulator is doing. Mine seems a little erratic but it's been that way for over 30 years with no problems.

 

[amraspalantir]

thanks guys for the replies.

 

[Pin_Head]

I prefer the amp meter. At a glance it will tell you if your alternator is working and if your battery is fully charged, which is more than a volt meter tells you.

 

[KOOTENAY KRUZER]

A voltmeter also tells you if your alternator is working. When the vehicle is not running it tells you the state of charge of the battery and when the vehicle is running it is telling you system voltage which tells you what the alternator/voltage regulator system is doing. The ammeter tells you the rate at which the battery is being charged/discharged. I want both, but I find that when driving I tend to refer to the voltmeter more than the ammeter - I refer to the ammeter when winching and doing anything else that loads the electrical system excessively.