Testing & TroubleshootingQuestion 501 of 521
You want to measure current with a DMM's internal ammeter function. Which practice is essential to avoid a dangerous fault?
a.Connect the meter in parallel across the load like a voltmeter
b.Connect the meter in series with the load, on the correct (fused) current jack, and never across a voltage source
c.Leave the leads in the current jacks while also measuring voltage
d.Use the 10 A jack for all measurements regardless of range
Explanation
An ammeter is a near-short internally, so it must be placed in series with the load using the proper fused current jack; connecting it in parallel across voltage (a) creates a bolted fault. Leaving leads in the current jacks while probing voltage (c) is a classic cause of arc-blast, and blindly using the 10 A jack (d) can bypass the fuse or misread small currents.
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