Dielectric test

Thread Starter


Joined Jan 26, 2020
Hi all

I need a clarification that i have designed a PCB board which has 4 layers, and no components has only holes with supply and ground.

My board has failed in dielectric test.

1) How much time i can test my board for dielectric test.(1,2,times..infinity??)
2) my conductors are so close, so that whether my pcb fails in dielectric.

What will be recommended gap is there any equation.


Joined Mar 30, 2018
Over stressing the insulation through prolonged application of a high voltage potential can weaken the properties of an insulator.

In safety type testing of a product, typically the test voltage is applied for one minute, but in a production environment 1 to 4 seconds is considered adequate.

As a general rule of thumb, a separation across a surface of 1mm should easily withstand a voltage of 1kV.

Solid insulation should be able to withstand 1.5kV (except for very thin material); a single layer of Sellotape can withstand 3kV.


Joined Jan 15, 2015
When we designed unusual motors dielectric testing was specified by the customer (end user). Our design was based to exceed their specifications. You should know the insulation properties of your board material and your design. As to equation it depends on many variables. Dielectric breakdown can be transitory or continuous and normally once an arc begins it is continuous.