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# What is creepage and clearance?

## What is creepage and clearance?

Clearance is the shortest distance in air between two conductive parts. Creepage distance means the shortest distance along the surface of a solid insulating material between two conductive parts.

What are the PCB creepage and clearance standards?

So what exactly are creepage and clearance, and when do you have to start thinking about them? Clearance – Clearance is the shortest distance in the air between two conductors. Creepage – Creepage is the shortest distance to another conductor along the surface of the insulating material of your PCB.

Is standard for creepage distance?

Specifically, creepage is the shortest distance between the path of two conductive parts of a medical device and is measures along the surface of insulation. The clearance is similar, but very different. It [creepage] is the shortest distance between two conductive parts, measured through air.

### Why is electrical creepage and clearance important?

Creepage & Clearance distances form part of the product’s electrical insulation system that protects the user from a Risk of Shock. For example, it is often necessary to measure the creepage distance between two traces across the surface of a printed circuit board.

How do you calculate creepage distance?

Adding the two figures together gives a total of 4.8 mm clearance distance. Similarly, if a voltage of 337 V rms was measured between the two pins of the switching transformer, Table IV (2L of the standard) must be used to calculate the creepage distance between the primary and secondary circuits.

What is the minimum clearance?

Maximum and minimum clearance The minimum clearance meanwhile is the difference between the lower bound of the orifice diameter and the upper bound of the shaft diameter. minimum clearance = minimum orifice diameter – maximum shaft diameter.

## How do you calculate minimum creepage distance?

What is electrical clearance?

The electrical clearance is the electrical isolation between two conductive components, whereas the creepage indicates the conduction of electricity across the surface of a nonconductive component. The clearance and creepage distance are two important parameters while designing an electrical assembly.

What is creepage current?

CREEPAGE: The shortest path between two conductive parts, or between a conductive part and the bounding surface of the equipment, measured along the surface of the insulation (Figure 2). One additional term that is related to these definitions in a high voltage design is “bounding surface.”

### What is protected creepage distance?

What is the creepage distance of insulator? Protected creepage distance of an insulator means part of the creepage distance on the illuminated side of the insulator which would lie in shadow if light were projected on to the insulator at 90°(or 45°in special cases) to the longitudinal axis of the insulator.

How is maximum clearance calculated?

Maximum and minimum clearance The maximum clearance of a fit is the difference between the upper bound of the orifice diameter and the lower bound of the shaft diameter. The minimum clearance meanwhile is the difference between the lower bound of the orifice diameter and the upper bound of the shaft diameter.

How is creepage measured in IEC 60601-1 third edition?

The clearance is similar, but very different. It [creepage] is the shortest distance between two conductive parts, measured through air. In IEC 60601-1 Third Edition, there are requirements for creepage distance and clearance, which follows the IEC “Modern Standard” approach.

## Why are creepage and clearance distances so important?

The isolation required between parts with different operating voltages, to prevent against unacceptable risk, is the primary reason for the importance of creepage and clearance distances. Specifically, creepage is the shortest distance between the path of two conductive parts of a medical device and is measures along the surface of insulation.

What is the clearance and creepage distance of insulation?

The clearance distance on the left is the distance of the “line of sight”, and the creepage distance path follows the contour of the groove. The clearance distance and creepage on the right is the distance of the “line of sight”. 5.

What are the clearance and creepage requirements for a circuit?

Consider a circuit where the clearance and creepage require­ments are defined as 4mm and 7mm, respectively. Now look at the designs in Figures 4 and 5.