Application Notes for UL Recongnized  Components Related  Standards

Standard No. UL1414 UL1449  ( 2nd EDition ) CSA VDE



Transient Voltage

Surge Suppressors

Accessories and Parts

for Electronic


Variators for use in

 Electronic equipment

File No. E165143 E150709 LR109736-1 21557-4790-0001
Symbols * * * *


Selection guide

  1. Determine the necessary steady-state voltage (working voltage).

  2. Establish the transient energy absorbed by the varistor.

  3. Calculate the peak transient current through the varistor.

  4. Determine power dissipation requirement.

  5. Select a model to provide the required voltage- clampling characteristics.