Dumb question: How to use a multimeter??
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jseber1982
Enterprise SCCM\SCOM
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that would be a very long tutorial and would give me sore hands trying to type it all. here is a link, just found it http://www.doctronics.co.uk/meter.htm
OK, basically a multimeter is a device for measuring a multitude of electrical and electronic things. For example, a multimeter usually includes a voltmeter (for measuring voltage, or potential difference as it is sometimes called), an ammeter (for measuring amps, which is electrical current), and an ohmmeter (not sure of the name or the spelling, but this measures electrical resistance). Some also can measure things to do with transistors, and both AC (alternating current, like the mains) and DC (direct current, like what a battery produces).
To use the device, usually you set it to whatever quantity you want to measure, for example volts, amps, or ohms, and select a sensitivity higher than what you expect to be measuring. So if you want to measure what you think might be a 12 V batter, you set it to whatever voltage is above 12 V. It might go up from 2 V, to 20 V, to 200 V, and in this case you set it to 20 V. (Always set it to higher to avoid causing damage to the multimeter.) You can then touch the two leads accross the battery and the display should show you the voltage. Depending on the meter, you may have to be careful to touch the leads the right way round, red to positive, black to negative.
As for it being digital, there is no difference in operation between an old style analogue meter and a digital one.
To use the device, usually you set it to whatever quantity you want to measure, for example volts, amps, or ohms, and select a sensitivity higher than what you expect to be measuring. So if you want to measure what you think might be a 12 V batter, you set it to whatever voltage is above 12 V. It might go up from 2 V, to 20 V, to 200 V, and in this case you set it to 20 V. (Always set it to higher to avoid causing damage to the multimeter.) You can then touch the two leads accross the battery and the display should show you the voltage. Depending on the meter, you may have to be careful to touch the leads the right way round, red to positive, black to negative.
As for it being digital, there is no difference in operation between an old style analogue meter and a digital one.
Just to add to what m3trj said, when you want to measure the voltage or resistance (ohm symbol) you connect the 2 leads to each side (nodes) of the component you are interested in.
For 'current', you use the multimeter to complete the circuit so to speak. This way, whatever current (electrons*-1) flowing through the circuit will flow through the multimeter and can be measured.
I can't remember exactly how a multimeter is designed, but I think for a resistance measurement it sends a small current across the component and measures the voltage drop - and calculates the resistance since it knows the current sent. Oh yeah, for this measurement make sure ur power to the circuit is off!
For 'current', you use the multimeter to complete the circuit so to speak. This way, whatever current (electrons*-1) flowing through the circuit will flow through the multimeter and can be measured.
I can't remember exactly how a multimeter is designed, but I think for a resistance measurement it sends a small current across the component and measures the voltage drop - and calculates the resistance since it knows the current sent. Oh yeah, for this measurement make sure ur power to the circuit is off!
So, if I wanted to test the resistance of something...what would I set it to? Obviously the ohms part of the dial, but how would I know which part?
And what are the other symbols on the dial? In the Amps section there is one spot marked 200u (not really a u, but as close as I can get)
and there are 2 sections on the dial that I am completely ignorant about. Looking at the pic above, they are in the 5 o'clock position.
The instructions that came with it consist of about 2 paragraphs and are totally unhelpful.
And what are the other symbols on the dial? In the Amps section there is one spot marked 200u (not really a u, but as close as I can get)
and there are 2 sections on the dial that I am completely ignorant about. Looking at the pic above, they are in the 5 o'clock position.
The instructions that came with it consist of about 2 paragraphs and are totally unhelpful.
u = Micro
So if there is a 200u in the Ampheres section, it means 200 micro ampheres. If you want to test the resistance, set it to the lowest range under ohms that doesn't give u an "overload" on the display. If you are not sure at all, start at the highest setting and work down
..
Lower settings will give u more resolution in the measurement - assuming the actual resistance is lower. e.g. if the compoennt resistance is 1527 ohms, set ur dial to 2000 instead of 200 or 20K.
And make sure ur power to the circuit is off!!.. for resistance
So if there is a 200u in the Ampheres section, it means 200 micro ampheres. If you want to test the resistance, set it to the lowest range under ohms that doesn't give u an "overload" on the display. If you are not sure at all, start at the highest setting and work down
..Lower settings will give u more resolution in the measurement - assuming the actual resistance is lower. e.g. if the compoennt resistance is 1527 ohms, set ur dial to 2000 instead of 200 or 20K.
And make sure ur power to the circuit is off!!.. for resistance
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