Tekmar tN4 User Switch - Three OUTPUTS. tekmarNet??4 User Switch 481 is a simple 3 button switch that provides an easy way to override system temperatures. With push of a button one can put all rmostats and boiler controls into an unoccupied" or away" state and take advantage of saving energy when building is not being used. buttons on this product are also programmable, allowing user to experience scenes within ir system. 481 has three output relays that can connect to alarm, paging, or home automation systems.