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Old 05-16-2004, 09:41 PM
KeithLambert7's Avatar
KeithLambert7 KeithLambert7 is offline
 
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KeithLambert7
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Steve,

I'm not entirely sure what you are checking out, so sorry if I'm off target here - but if it's voltage...

First, most DVOM's (even the ones for $19.99) are internally fused, so don't worry too much about it. You won't blow the meter maybe just a fuse within it, and then usually only if you have a direct short somewhere or set the range of the meter too low for the volts you are working with.

If you are checking ampre draw (how much current is passing through a point) -which the pelican thread wasn't doing - then you really need a amprobe clamp meter (I have one you're welcome to use).

But if you are checking voltage not amps from point to point, then the DVOM meter you have works fine. Make sure the meter's voltage range you select goes higher than 15 volts when working with the alternator.

In order to test voltage at different points in the circuit, put the (negative) black lead on an earth ground, like the (-) post of the battery or another clean metal point such as the deck lid hinge. Then touch the red lead to the wire or connector you want to check the voltage.

The meter itself has a very high impedance, and doesn't draw current by itself, this makes it possible to check beteen the two posts of a battery without causing a short or high current draw. You do NOT want to put the meter 'in-line' with a battery wire, or you will subject the meter and it's measly 16 ga. wires to the same current as the much larger battery cables - sure to cause a major problem. Testing from point 'a' to ground, or point 'b' to ground will allow you to test the voltage on about anything (even the 200amp main in your house - though best left to your electrician)

Keep in mind however that on some newer cars like the 996, the small voltage generated by the battery in some meters fed in the wrong direction could blow the delicate electronics of some modern CMOS chips in cars. So beware as the meter can be used in some - but not all places on some of these cars.

Hope that helps, and please someone correct me on any errors....etc

Keith
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