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标题: How to Test Communication Relay with Multimeter – A Step-by-Step Guide Communication relays are essential components in many electronic and telecommunication systems. They act as electrically operated switches, allowing low-power signals to control high-power circuits. Over time, relays can wear out or malfunction due to coil failure, contact corrosion, or mechanical issues. Testing a communication relay with a multimeter is a simple and effective way to ensure it operates correctly before installing it in a circuit or diagnosing system issues. This article provides a comprehensive step-by-step guide to testing communication relays using a standard multimeter.