Multimeters, such as the Fluke 87V or the Flir DM92, are an essential tool used by electricians, technicians, and engineers. For safe operation of a multimeter, it is important to perform a visual inspection and simple electrical test prior to its use.
First, inspect the test leads to make sure they are grease and dirt-free. Clean if necessary before proceeding. Next, look for any cracks, missing insulation or damaged tips. If the probes do not pass the visual inspection, they should be replaced.
Upon passing visual inspection, turn the multimeter on and set the selector switch to the ohms function. With the test leads in the appropriate connection jacks, take the free ends of the leads and touch them together. A resistance reading of a few tenths of an ohm should be displayed. With the free ends still touching move the leads around to make sure there are not any intermittent connections.
If the readings jump around or the displayed resistance value is above a couple ohms, the leads should be replaced. Once these tests pass, then the meter and probes are ready for safe use.