1769205x2, 176881212, 176861512

FISM

– Fixed Isolated SMT Module

we-online.com

Würth Elektronik eiSos GmbH & Co. KG

– Data Sheet Rev. 1.0

©July 2018

10/37

DIELECTRIC STRENGTH TEST SETUP (HIGH POT TEST)

Connect all input

– and output terminals together (see figure below) before connecting the supply voltage. When testing, set

the cut-off current to 1mA.

+VIN

-VIN

-VOUT

+VOUT

Module

2

1

4

5

Sup ply

Parameters Supply Device: Current limit set 1mA, Test voltage 2000Vdc, Test time 1sec.

REPEATED HIGH-VOLTAGE ISOLATION TESTING

A repeated high voltage test of a barrier component will degrade its isolation capabilities.

The primary and secondary windings within this transformer are enameled (coated) but do not possess additional isolation.

Typically, parts can withstand many times their stated test voltage and still perform optimally. The magnet wire coating can

degrade over time due to chemical reactions that occur at high voltages. We recommend keeping high voltage isolation

testing to a minimum to better protect the isolation between the windings. If repeated high voltage isolation testing is

required, consider reducing the voltage by a significant amount e.g. 20% from the test voltage stated within the datasheet.

These safety concerns are equally applicable to components that utilize functional isolation beyond wire coating (i.e.

physical barriers or spacing).