TeSys LT3 thermistor protection unit for use with PTC probes, with manual reset and fault indicator on front, dual voltage supply 24 or 48V AC 50/60Hz.To be used with a combination of PTC probes impedance lower than 1500 Ohm at 25°C, the trip impedance zone is 2700-3100 Ohm, the manual reset is possible only if impedance has decreased enough to be below 1500-1650 Ohm.It provides 2 auxiliary contacts 1NO 1NC for fault signalling, 1 pushbutton on front face for a local manual reset, and 1 logic input for connection of a remote reset button.DIN rail mounting, connections by cage terminals.PTC thermistor probes DA1TT, DA1TS available (to be ordered separately).Multi standards certified (IEC, UL, CSA), Green Premium compliant (RoHS/REACh).