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标题: How to Test Industrial Relay with Multimeter: A Step-by-Step Guide Industrial relays are essential components in many electrical and automation systems. They act as electrically operated switches, allowing low-voltage circuits to control high-voltage equipment safely. Over time, relays can wear out, their contacts can become corroded, or their coils can fail. Therefore, it is crucial to know how to test an industrial relay with a multimeter to ensure that your system operates reliably and safely. This article provides a step-by-step guide for testing industrial relays using a digital multimeter.