Do Reed Relays Require a Wetting Current or Other Minimum Switching Requirements?

Updated May 2, 2018

Reported In


  • Reed Switch

Issue Details

I know that some NI switches specify a minimum switch load or wetting current to successfully operate the relays. Do NI switches featuring reed relays have these minimum requirements?


No, reed relays do not have minimum switching requirements or wetting currents. Other switches may specify these minimum requirements because low voltage or current switching signals do not have the ability to vaporize pollutants that can accumulate on the mechanical components of the relay, preventing them from operating. This is not an issue with reed relays because they are contained in a glass container which is filled with an inert gas.  This removes the need for any wetting current, as there are no pollutants that can build up on the relay to prevent the mechanical action from occurring.