Cracking issue on Vishay WSL series Resistors

WSL Series Power Metal Strip Resistors from Vishay use welded construction and are ideal for all types of current sensing, voltage division and pulse applications. Sometimes, we hear from a customer who finds cracking on these resistors and worries about its effect on the resistor’s performance.

This cracking would be cosmetic for the WSL series. Refer to below WSL series construction, which includes:

  • Resistive element
  • Copper Terminal with solderable finish
  • Terminal to Element weld
  • High temperature encapsulant

This cracking is only a coating that is within the laser trim space, and it will have no performance issues. If the cracking is on the chip resistor, it would be a problem. However the all metal welded construction is different and a cosmetic issue.