The Murphy MS2120 is a is a multi-purpose Tattletale with dry contacts that can be used to make two circuits and break another when tripped. Operates from Magneto Ignition. The operating coil is intermittent duty and must be disconnected by an external circuit when tripped. The MS2120 features a manual indicating reset type and a weather resistant case with screw terminals for ease of customer hookup. The control circuit output contacts are NCG and NOG. Dry contacts normally wired in ground circuit. The latch type is energize to trip.
Tattletale Annunciator indicates which monitored function failed leading to the alarm or shutdown whereas magnetic switches do not. Magnetic switches operate basically as a latching relay. The MS2120 is a replacement for 307, 307PH and 224.