Metal Oxide Varistors (MOVs) LST Varistor Series > SPD Thermally Protected Varistor Pb RoHS LST Varistor Series Description The LST Varistor Series is constructed with Littelfuses renowned thermally protected varistor technology (TMOV). The built-in thermal disconnecting function and electric arc shield prevent catastrophic failure and fire hazard even under the extreme circumstances of varistor end-of-life or abnormal overvoltage conditions. It is specifically designed as a Type 1 Component Assembly Surge Protective Device (SPD) and is suitable for Type 1 and Type 2 SPDs. Features Short Circuit Current Rating (SCCR) of 200 kA and Nominal Discharge Current Rating (I ) of 20 kA Agency Approvals n Available in both Maximum Discharge Current (I ) ratings max Agency Standard Agency File Number of 50 kA and 75 kA. Both ratings utilize the same footprint and PCB layout UL1449 E320116 Mechanically triggered AC and DC rated micro-switch with Normally Open or Normally Closed options for remote indication and/or monitoring circuit Typical Circuit Diagram with Normally Open Switch Visual tab option to display LST working status RoHS compliant, Lead-free, and Halogen-free Primary Side Secondary Side Contact Lead UL Recognized to UL 1449 and CSA C22.2 No. 269.4 as a Type 1 Component Assembly (Type 1CA) Thermal C (Common) Disconnector Power NO (Normally Open) To Protected Device Source Benefits Metal Oxide Varistor (MOV) Thermal Suitably rated for Type 1 and 2 SPD applications Connection Isolation Same PCB layout/design for 50 kA and 75 kA I MOV Lead max Galvanic Isolation rated SPDs Note: More flexibilities/options for designing an isolated remote This typical circuit shows how the switch pins (C and NO) can be used to indicate the indication/monitoring circuit connection status of thermal disconnector for remote indication. This denotes that the circuit will be no longer protected from surge currents by the MOV after the thermal disconnector Clear indication for technician/engineer to replace EOL forms open circuit. product to continue surge protection for the end product Environment-friendly Facilitate meeting UL 1449 or CSA C22.2 No. 269.1 and Applications 269.2 for Type 1 or Type 2 SPDs Type 1 and Type 2 Surge Protective Devices (SPDs) General Technical Specification Standard Units Climatic Category IEC 60068-1 40/85/56 Operating Temperature IEC 61051-1 -40 C ~ +85 C Storage Temperature -40 C ~ +85 C Voltage Proof IEC 61051-1 2.5 kVRMS Insulation Resistance IEC 61051-1 100 M 2021 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 02/18/21Metal Oxide Varistors (MOVs) LST Varistor Series > SPD Thermally Protected Varistor Electrical Specifications Specifications (85 C) Specifications (25 C) Nominal Maximum Continuous Discharge Voltage Maximum Peak Surge Current Operating Voltage Current Protection Short Circuit (8/20 s, 1 Pulse) Part Number (MCOV) (8/20 s, Rating Current Rating 15 Pulses) V I I VPR SCCR RMS max n ( V ) ( kA ) ( kA ) ( V ) ( kA ) LST1505VL2NT1 150 50 20 600 200 LST1507VL2NT1 150 75 20 600 200 LST1805VL2NT1 180 50 20 800 200 LST1807VL2NT1 180 75 20 800 200 LST2755VL2NT1 275 50 20 900 200 LST2757VL2NT1 275 75 20 900 200 LST3205VL2NT1 320 50 20 1000 200 LST3207VL2NT1 320 75 20 1000 200 LST3855VL2NT1 385 50 20 1500 200 LST3857VL2NT1 385 75 20 1500 200 LST4205VL2NT1 420 50 20 1500 200 LST4207VL2NT1 420 75 20 1500 200 LST5105VL2NT1 510 50 20 1500 200 LST5107VL2NT1 510 75 20 1500 200 LST5505VL2NT1 550 50 20 1500 200 LST5507VL2NT1 550 75 20 1500 200 LST6905VL2NT1 690 50 20 2000 200 Note: For LST***7 device with Imax 75 kA rating, thermal disconnector may safely open circuit without any damage to the device after Imax test. Switch Function Configuration Switch Functions Switch Pins Connected to Signal Circuit Normally Open C and NO Normally Closed C and NC Normally Open & C and NO: Normally Open monitoring circuit Normally Closed C and NC: Normally Closed monitoring circuit No Function No switch pin Normally-open and/or normally-closed switch functions are available for remote indication circuit to identify LST working status Switch pins of Common (C) and Normally-Open (NO) can be connected together for normally-open monitoring circuit Switch pins of Common (C) and Normally-Closed (NC) can be connected together for normally-closed monitoring circuit Electrical rating for switch pin: 60 Vdc/0.2 A, or 250 Vac/0.1 A Visual Tab within housing: LST is still functional Visual Tab shows up (Optional): LST has been activated and needs to be replaced 2021 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 02/18/21