Creepage / Clearance distance checking tool

Current Sensors

AKM's coreless current sensor IC "Currentier" has insulation performance compliant with UL61800-5-1. It is safe to use due to its unique package structure, which has no creepage distance or clearance distance inside. This page introduces a tool that allows you to calculate the insulation performance (creepage and clearance distances) required by the current sensor to comply with UL61800-5-1, according to your application environment. (You will need to register with myAKM to use this tool.)

How to use the tool

The "Creepage Distance and Clearance Distance Calculation Tool" allows you to calculate the creepage distance and clearance distance required for insulation in accordance with UL61800-5-1 by entering your operating environment, and also to check whether AKM current sensors meet the requirements.

The required creepage and clearance distances will vary depending on the environment and type of insulation used. (See the bottom of the page for "creepage distance" and "clearance distance".)


Enter the input fields

(1) In the input field, enter / select the following five items, (2) and finally click the Calculate button.

- System voltage

- Operating voltage

- Overvoltage category

- Pollution degree

- Insulation

Check the output fields

The calculation results are shown in the output columns (3)(4)(5).

(3) Creepage and clearance distance required for insulation in your operating environment

(4) AKM product series name and its creepage and clearance distance

(5) Confirmation of whether AKM's current sensor satisfies the performance in your operating environment

Our current sensors (CZ372, CZ370 series and CZ3A series) are a member of material group 2 and have a creepage / clearance distance of 8mm or more.

If the calculation result is less than 8mm, it will be displayed as OK, and if it is more than 8mm, it will be displayed as NG.

Different material groups require different creepage / clearance distances. * A Material Group is a classification of insulating materials according to the ease with which electricity runs on the surface (CTI value).

The Material Groups of general current sensors are as follows.

Material Group 1 : CTI≧600  

Material Group 2 : 400≦CTI<600

Material Group 3a : 175≦CTI<400

Material Group 3b : 100≦CTI<175

Download tool

Application Note

Creepage / Clearance distance checking tool

(1524 KB、zip file)

Please fill in the following form and send it to us.

A URL for downloading will be sent to your registered email address.

This tool should be used on your PC.



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Current sensor and insulation

Creepage distance and clearance distance are the shortest distances between the conductive parts required for insulation.


Creepage distance: the shortest distance along the insulation material between the conductive parts

Clearance distance: The shortest spatial distance between the conductive parts


AKM's current sensors can define a creepage distance and a clearance distance by the distance between the primary and secondary terminals. AKM's current sensors have a unique (patented) package structure that has no internal creepage or clearance distances. Compared to the case where creepage and clearance distances exist inside the package, higher reliability is ensured over the long term.

For more information, please click here.


In addition, by ensuring insulation, AKM's current sensor can contribute to solving the following issues.