Using IPC-2221 as the reference standard, we can find the minimum required clearance and creepage distances: However, since the PCB will be used at an altitude of 2000m, we need to adjust the clearance distance. According to IPC-2221, for altitudes between 1000m and 3000m, the clearance distance should be multiplied by a factor of 1.48.
1. Voltage The voltage between conductive parts is a primary factor in determining the necessary clearance and creepage distances. Higher voltages require greater distances to prevent electrical breakdown and surface leakage currents. 2. Pollution Degree
To ensure the safety and reliability of electrical equipment, various standards and guidelines provide recommendations for clearance and creepage distances. Some of the key standards include: IEC 60664-1: This international standard provides guidelines for determining clearance and creepage distances in low-voltage equipment.
Now, let’s consider the same device with a working voltage of 250 V AC, a pollution degree of 2, and an insulating material from Material Group IIIa. To find the minimum creepage distance, we can use Table 2 below, which is also adapted from the IEC 60664-1 standard: For our example, the minimum required creepage distance is 4.0 mm.
Consider an electrical device with a working voltage of 250 V AC and a pollution degree of 2. To determine the minimum clearance distance, we can refer to Table 1 below, which is adapted from the IEC 60664-1 standard: Based on the table, the minimum required clearance distance for our example is 1.5 mm.
In an isolated power supply (or any isolated system), this is a standard technique to increase creepage distance. Reduce manual routing time for even the most complex projects. After operating voltage, the most significant factor in the clearance and creepage requirements for a printed circuit board comes from the material properties of your PCB.