What condition usually indicates that a grounding cell may be malfunctioning?

A high resistance reading is typically indicative of a malfunctioning grounding cell. A properly functioning grounding cell should have low resistance, allowing for effective grounding and proper current flow. When the resistance reading is high, it can signal that there is a poor connection or that the grounding cell is corroded or damaged. This high resistance can lead to inadequate grounding, which can cause safety hazards and jeopardize the effectiveness of corrosion control measures.

In contrast, consistent voltage output usually indicates that the grounding cell is operating correctly, while low temperature on contact points does not provide relevant information regarding the functionality of the grounding cell. Excessive noise during operation may also suggest issues, but it is not as directly linked to the critical function of the grounding resistance as a high resistance reading is. Thus, the best indication of a malfunctioning grounding cell is shown by high resistance readings.