4 ms·the only true binary sensor i can think of are good old fashioned mechanical switches.by choonway 5y agothe only true binary sensor i can think of are good old fashioned mechanical switches.samatman 5y agoMercury switch on a bimetallic strip (old-school thermostat) counts, same basic principle.stingrae 5y agoreed switchrelaxing 5y agois an old fashioned mechanical switch.