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Can u guys tell me wat is multimeter n wat is voltmeter gauge use for.Can multimeter use to check battery.Or can check anything abt electrical.Do voltmeter do the same thing as multi meter.Confuse. :roll:
 

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A multimetre is used to check lots of different functions, a voltmetre is used to check only voltage.
 

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Need Constant Supervision
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A mutlimeter can measure different types of readings normally in Ohms, Amps or Volts. This is a multimeter...



As you can see it can also do several variations of measurement depending on the current, resistance etc you testing.

A volt meter can also look like the meter above or you can get a basic simple one like you would find in older cars like this..



All it does is give you a volt reading. Hope the above helps.
 

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A Multimeter usually reads Voltage & Current, plus maybe some other functions depending on how posh it is.

Put very basically...A voltmeter has a relatively HIGH resistance and is placed across the power source, eg battery.

An ammeter has a LOW resistance and is placed in line with a circuit to measure what is going through it.

NB Don't ever put an ammeter across a power source because since it has a low resistance, a very large current wil flow and you'll f*** it (if it hasn't got a fuse/trip in it)

An ohm meter reads resistance, because the meter has a battery in it and it can see how much current flows for a given voltage (Good old Ohms law R=V/I)
 
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Maverick said:
A volt meter can also look like the meter above or you can get a basic simple one like you would find in older cars like this..

Some people recommentd a charge monitor like the Dyna Charge monitor. If you have a volt meter like above, do you really need it? Or does that just measure what's in the battery?

Wow, I feel dumb asking that kinda question...
 
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lol

macosie said:
Some people recommentd a charge monitor like the Dyna Charge monitor. If you have a volt meter like above, do you really need it? Or does that just measure what's in the battery?

Wow, I feel dumb asking that kinda question...
apparently no one esle knows either... lol
 

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Sorry did not spot this one untill now... :oops:

There was a very informative post done on the Dyna Charge Meter HERE by GSPD.

A simplistic volt meter as above would give you different readings from when you just switched the bike on to starting the motor. The needle should move up to the positive side whilst riding showing the additional charging current, when the motor is not running it will merely display what ever charge is left in your battery. So it's basically doing the same thing as the Dyna Charge Meter except there is no display lights telling you that your battery is about to die or there the rectifier is on it's way out. You have to make those assumptions yourself looking at the voltmeter.

This is as basic as I can explain it and hopefully correct so please if any leccie guys out there can do better help.
 

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Maverick said:
when the motor is not running it will merely display what ever charge is left in your battery
Ah, now we're getting to the heart of the matter :shock:

A voltmeter ALONE can't show whether there is a big or small charge in a battery ....a knackered battery may give a nice voltage reading when you put a meter across it even when it contains little charge (because the meter has a high resistance, so it isn't drawing any current).

The real test is to make the battery do some work, which is why auto electricians have a big W-shaped resistor with a voltmeter across it. If the volts stay up when the battery is pushing out a healthy current, then it has a good charge.


(To put this in everyday terms, a useful measure of how good your battery is, would be to see how the volts hold up WHILST you're turning the engine over).

HTH :?
 

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Hmm, since this is quite a complex subject and I was talking in general terms, I'd better add a bit more to clear up any confusion. (and try to dodge any flak :roll: )

My last post referred to checking the charge in a battery, for which a voltmeter alone doesn't tell you much. The best check for the health of a battery ? - In the old days you could dip the cells with a hygrometer to check the specific gravity, and this would tell how healthy the electrolyte was (as well as the charge state to some extent) ....but.... nowadays most modern batteries are sealed, so that one's out :roll:

A slightly different subject was the The Dyno Charge Meter. This is wired into the bike and is looking at the output from the alternator and whatever effect all the electrical loads are having on it. Obviously the voltage should be higher than the battery static voltage with the engine running since the battery needs a higher voltage than its own (thoeretical) 13.8v in order to be charged. However if the alternator is faulty and is putting out too high a voltage it will 'cook' the battery and other components. Even though this gadget is called a 'Charge Master' it isn't measuring charge, it just shows that the alternator output is healthy, so that a voltage is available for charging the battery.

BUT Any old £1.50 bog-standard voltmeter will show this, I've even got a voltmeter built into my Garmin GPS

And finally a thought about batteries........ Just because the voltage with the engine running is healthy, it doesn't mean that the battery is taking a charge. If it's healthy then it should do, and even then if it does take a charge it may not necessarily hold it

HTH & Have a nice day
 

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Any thoughts on how long, with the bike left completely idle, the battery should still hold enough oomph to start her up?
 

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Whealie said:
Any thoughts on how long, with the bike left completely idle, the battery should still hold enough oomph to start her up?
I've got an Optimate because I don't want to put it to the test !!! But I would guess that in Summer (batteries hate the cold) you should get at least a couple of months if you've got nothing connected when the ignition is off.

I've heard that that some bike alarms can really discharge a battery.

If you're mystified as to why you're battery keeps running down, my first move would be to remove the +ve battery lead and put an Ammeter in line with it. With the ignition off there shouldn't be any significant current - if there is then you'll have to get a wiring diagram and track down where the culprit is.

If that's OK, reconnect the +ve lead. clip a Voltmeter across the battery. Measure the voltage, then start the bike. The volts should rise with the engine running (higher revs than idle though) telling you that the alternator is outputting correctly.

If all of this checks out OK, I'd begin to suspect the battery. Take it to a decent battery place and ask them to check it ......BUT don't let them fob you off with the spotty teenager brandishing a multimeter, because as we've mentioned in the previous posts a straght voltage reading tells you nothing about the condition of the battery, it needs to be checked under load.

HTH
 
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