Metal-Oxide Varistors (MOVs) Thermally Protected Varistors > SMOV 25S Varistor Series RoHS SMOV25S Varistor Series Description The Littelfuse SMOV 25S thermally protected varistor is a self-protected device. It consists of a 25mm square varistor with an integral thermal disconnect designed to open in the event of overheating due to abnormal overvoltage as outlined in UL1449. The SMOV helps facilitate SPD module compliance to UL1449 and offers quick thermal response due to the close proximity of the integrated thermal element to the MOV body. This configuration also offers lower inductance than most discreet solutions resulting in improved clamping performance to fast over voltage transients. The device has a separate micro-switch, which can be used to indicate that the MOV has been disconnected from the circuit. This separate switch makes the monitoring circuitry completely isolated from the main power which ensures indicator circuit safety and Agency Approvals simplifies the customers circuit design. Agency Agency Approval Agency File Number Features UL1449 E320116 Maximum single Recognized to UL 1449. surge capability 20 kA, Lead-Free and RoHS 8/20 waveshape. compliant. Nominal Discharge Additional Information Integrated micro-switch for Current Value: 10kA. indication circuitry/design. Intermediate current rating: 50A/150A. -45C to +75C operating Datasheet Resources Samples temperature. Applications SPD applications AC/DC distribution IT/Data center Power supplier Telecommunication Absolute Maximum Ratings For ratings of individual members of a series, see Device Ratings and Specifications chart. Units SMOV25S Varistor Series Continous: Steady State Applied Voltage: DC Voltage Range (VM(DC)) 150 to 970 V AC Voltage Range (V ) 115 to 750 V M(AC)RMS Transient: Non-Repetitive Surge Current, 8/20s Waveform (I ) 20,000 A TM Non-Repetitive Energy Capability, 2ms Waveform (W ) 170 to 670 J TM Operating Ambient Temperature Range (T ) -45 to +75 C A Storage Temperature Range (T ) -45 to +85 C STG Hi-Pot Encapsulation (Isolation Voltage Capability) 2500 V Isolation Voltage Capability (when the thermal disconnect opens) 1500 V Housing Insulation Resistance >1,000 M CAUTION: Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. 2017 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 09/14/17Metal-Oxide Varistors (MOVs) Thermally Protected Varistors > SMOV 25S Varistor Series Device Ratings & Specifications Maximum Rating (75C) Specifications (25 C) Continuous Transient Varistor Maximum Typical Voltage at Clamping Capacitance Peak Surge Nominal Part 1mA Test Voltage AC DC Energy f = 1MHz Current Discharge Number Current 8/20s Volts Volts 2ms 8/20s Current (In) I V V TM N(DC) N(DC) V V W In Vc I C M (AC) M(DC) TM PK 1 Pulse Min Max (V) (V) (J) (A) (A) (V) (V) (A) (pF) SMOV25S111MP 115 150 170 20000 10000 162 198 295 100 3200 SMOV25S111NP SMOV25S131MP 130 170 190 20000 10000 184.5 225.5 335 100 2800 SMOV25S131NP SMOV25S151MP 150 200 220 20000 10000 216 264 390 100 2300 SMOV25S151NP SMOV25S181MP 175 225 250 20000 10000 243 297 450 100 1900 SMOV25S181NP SMOV25S251MP 250 320 330 20000 10000 351 429 640 100 1400 SMOV25S251NP SMOV25S271MP 275 350 350 20000 10000 387 473 700 100 1250 SMOV25S271NP SMOV25S301MP 300 385 370 20000 10000 423 517 765 100 1150 SMOV25S301NP SMOV25S321MP 320 420 390 20000 10000 459 561 825 100 1080 SMOV25S321NP SMOV25S421MP 420 560 460 20000 10000 612 748 1100 100 820 SMOV25S421NP SMOV25S461MP 460 615 490 20000 10000 675 825 1220 100 750 SMOV25S461NP SMOV25S511MP 510 670 520 20000 10000 738 902 1335 100 680 SMOV25S511NP SMOV25S551MP 550 745 550 20000 10000 819 1001 1475 100 630 SMOV25S551NP SMOV25S621MP 620 800 600 20000 10000 900 1100 1625 100 550 SMOV25S621NP SMOV25S751MP 750 970 670 20000 10000 1080 1320 1950 100 460 SMOV25S751NP Average power dissipation of transients should not exceed 1.5 watts Same ratings and specifications apply to Non Isolated Monitored Switch alternative design. Replace with in the part number. e.g.: SMOV25S111NP. Refer to Part Number System at the end of this document. 2017 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 09/14/17