...R3 STEP 2 - Set the DIP Switch on the SP390A - R3 SET THE DIP SWITCH ( SP390A - R3 ) NOTE : If you have the SP385A - R3 , you can skip this step . Set the DIP switches on the SP390A - R3 for 2 - or 4 - wire operation . TABLE 1 . SP390A - R3 DIP SWIT...