This plug-on relay interface is PAKNET compatible and plugs on to the STU pins on a CASTLE CARE-TECH 2200, 2300, 2500, 2700 or 3000 MERiDIAN control board to give 3 sets of changeover contacts (PA, INTRUDER and SET) plus line fault input and 10-pin output connector for PAKNET or DIGI.
