A capacitor can be tested using a megohmmeter, an ohmmeter, or a digital multimeter. If a digital multimeter set up as an ohmmeter is connected to a shorted capacitor, what would the display indicate?
• Behavior of a short circuit when measured with an ohmmeter or DMM (digital multimeter) in resistance mode • Normal charging behavior of a good capacitor when measured with an ohmmeter (resistance starts low, then changes) • Meaning of a DMM display showing OL (over limit / open circuit) versus a very low resistance reading
• First, think about what resistance the meter actually "sees" if the capacitor is shorted inside—does that look like an open circuit or a direct connection? • Recall how a good, unshorted capacitor behaves when you connect an ohmmeter across it—what happens to the resistance reading over time? Would a shorted capacitor behave the same way? • Match each answer choice with either: (1) an open circuit, (2) a normal capacitor charging, or (3) a direct short. Which matches the situation in the question?
• Be clear on what OL represents on most digital multimeters in ohms mode (open / out-of-range high resistance, not low). • Remember that a short should appear as a very low resistance path to the meter, not as an open circuit. • Ask yourself whether there is any change over time when the meter is connected to a pure short, or if the reading would simply stay where it starts.
No comments yet
Be the first to share your thoughts!