What is the minimum insulation resistance value for most circuits?

The minimum insulation resistance value for most circuits is typically set at 1 MΩ. This value is crucial for ensuring safety and proper functioning in electrical systems. Insulation resistance measures the effectiveness of the insulation material in preventing electrical leaks, which can pose serious safety hazards, including electric shocks or fire risks.

Setting the minimum insulation resistance at 1 MΩ helps to ensure that there is sufficient resistance to guard against these potential issues. In practice, if the insulation resistance falls below this threshold, it may indicate a deterioration of the insulation material, which can lead to failures or hazardous conditions.

While higher values such as 2 MΩ, 5 MΩ, or even greater might be employed in certain applications or more stringent standards, 1 MΩ serves as a widely accepted baseline for many general electrical systems, making it a standard reference for safety and performance assessments.