What type of Multimeter is safe to use on computers?

Posted by Ssvarc on Super User See other posts from Super User or by Ssvarc
Published on 2010-01-15T20:11:28Z Indexed on 2010/04/21 0:13 UTC
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In "Upgrading and Repairing PC's - 18th edition" by Scott Mueller on pg. 1278 he discusses multimeters. "You should only use a DMM (digital multimeter) instead of the older needle-type multimeters because the older meters work by injecting 9V into the circuit when measuring resistance, which damages most computer circuits. A DMM uses a much smaller voltage (usually 1.5V) when making resistance measurements, which is safe for electronic equipment."

  1. Most DMM's that I've looked at have 9V batteries. Are they internally stepping down the voltage used when making these measurements?

  2. Wouldn't the concern of injecting 9V be true when measuring continuity as well?

  3. A little off topic, there is a fascinating way to test for laptop screen inverter failure, (http://www.fonerbooks.com/test.htm), is anyone aware of a safe DMM that is capable of this as well?

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