S 34S Varistor Series RoHS Description The Littelfuse S 34S thermally protected varistor is a self-protected device. It consists of a 34mm square varistor with an integral thermal designed to open in the event of overheating due to abnormal overvoltage as outlined in UL1449. The S helps facilitate SPD module compliance to UL1449 and offers quick thermal response due to the close proximity of the integrated thermal element to the body. This configuration also offers lower inductance than most discreet solutions resulting in improved clamping performance to fast over voltage transients. Agency Approvals Agency Agency Approval Agency File Number The device has a separate micro-switch, which can be used to indicate that the has been ed from the circuit. This separate switch makes the monitoring circuitry completely isolated from the main power which ensures indicator circuit safety and simplifies the customers circuit design. Features UL1449 Additional Information Datasheet Resources E32116 Samples Maximum single surge capability 4 ka, 8/2 waveshape. Nominal Discharge Value: 2kA. Intermediate current rating: 5A/15A. -45 C to +75 C operating temperature. Applications Recognized to UL 1449. Lead-Free and RoHS compliant. Integrated micro-switch for indication circuitry/design. SPD applications AC/DC distribution T/Data center Power supplier Telecommunication Absolute Maximum Ratings For ratings of individual members of a series, see Device Ratings and Specifications chart S34S S Varistor Series Units Continous: Steady State Applied Voltage: DC Voltage Range (VM(DC)) 15 to 97 V AC Voltage Range (V M(AC)RMS ) 115 to 75 V Transient: Non-Repetitive Surge, 8/2µs Waveform (I TM ) 4, A Non-Repetitive Energy Capability, 2ms Waveform (W TM ) 28 to 12 J Operating Ambient Temperature Range (T A ) -45 to +75 C Storage Temperature Range (T STG ) -45 to +85 C Hi-Pot Encapsulation (Isolation Voltage Capability) 25 V Isolation Voltage Capability (when the thermal opens) 15 V Housing Insulation Resistance >1, MΩ 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.
Device Ratings & Specifications Maximum Rating (75 C) Specifications (25 C) Part Number S34S111MP S34S111NP S34S131MP S34S131NP S34S151MP S34S151NP S34S181MP S34S181NP S34S251MP S34S251NP S34S271MP S34S271NP S34S31MP S34S31NP S34S321MP S34S321NP S34S421MP S34S421NP S34S461MP S34S461NP S34S511MP S34S511NP S34S551MP S34S551NP S34S621MP S34S621NP S34S751MP S34S751NP AC Volts V M (AC) Continuous DC Volts Energy 2ms Transient Peak Surge 8/2μs Nominal Discharge Varistor Voltage at 1mA Test Maximum Clamping Voltage 8/2μs Typical Capacitance f = 1MHz I V M(DC) W TM TM In Vc I RMS 1 Pulse Min Max PK C (V) (V) (J) (A) (A) (V) (V) (A) (pf) 115 15 28 4 2 162 198 35 2 115 13 175 31 4 2 184.5 225.5 345 2 15 2 36 4 2 216 264 45 2 8 18 24 4 4 2 256 312 488 2 68 25 32 49 4 2 351 429 65 2 5 275 35 55 4 2 387 473 73 2 45 3 385 59 4 2 432 528 78 2 45 32 42 64 4 2 459 561 83 2 38 42 56 91 4 2 612 748 113 2 3 46 61 96 4 643.5 786.5 1188 2 28 51 675 96 4 738 92 135 2 25 55 7 965 4 77 939 1415 2 225 62 8 11 4 9 1 1625 2 2 75 97 12 4 18 132 2 2 18 Average power dissipation of transients should not exceed 2. watts Same ratings and specifications apply to Non Isolated Monitored Switch alternative design. Replace "M" with "N" in the part number. e.g.: S34S111NP. Refer to Part Number System at the end of this document. V N(DC) V N(DC)
Characteristics Peak & Energy Derating Curve 1 (A) 1 Typical 1 A 5 A 2.5 A.5 A PERCENT OF RATED VALUE 8 6 4 2 Figure 1.1 1 1 Time (secs) Figure 2-45 5 6 7 8 9 11 12 13 AMBIENT TEMPERATURE (ºC) For applications exceeding 75ºC ambient temperature, the peak surge current and energy ratings must be reduced as shown. Pulse Rating Curve SURGE CURRENT (A) 5, 1 2, 2 15 1, 5, 12 2, 1 3 1, 1 4 5 2 5 2 INDEFINITE 1 5 1 6 Figure 3 1 2 1, 1, IMPULSE DURATION ( µs) Transient V-I Characteristic Curve Maximum Clamping Voltage TA = -45 C to 75C Voltage - VOLTS V661 V681 V751 V511 V551 V571 V481 V111 V141 V131 Figure 4 V441 V421 V151 1mA 1mA ma 1A 1A A A A A - AMPS V391 V351 V331 V321 V31 V271 V251 V21 V181
Wave Solder Profile Because the S 34S varistors contain a thermal protection device, care must be taken when soldering the devices into place. Two soldering methods are possible. Firstly, hand soldering: It is Non Lead free Profile recommended to heat sink the leads of the device. Secondly, wave soldering: It is critically important that all preheat stage and the solder bath temperatures are rigidly controlled. Lead free Profile 3 25 Maximum Wave 24C 3 25 Maximum Wave 26C TEMPERATURE (ºC) 2 15 TEMPERATURE (ºC) 2 15 5 5.5 1 1.5 2 2.5 3 3.5 4.5 1 1.5 2 2.5 3 3.5 4 TIME(MINUTES) TIME(MINUTES) Figure 5 Figure 6 Physical Specifications Environmental Specifications Lead Material Soldering Characteristics Insulating Material Device Labeling Tin plated Copper Solderability per MIL STD 22, Method 28 Cured, flame retardant epoxy polymer meets UL94V requirements. Marked with LF, part identifier, and date code Operating/Storage Temperature Humidity Aging Shock -45 C to +75 C/ -45 C to +85 C +75 C, 85% RH, hours +/-1% voltage +75 C to -4 C 5 times +/-1% voltage Solvent Resistance MIL STD 22, Method 215 Moisture Sensitivity Level 1, J-STD-2 Part Numbering System Part Marking System DEVICE FAMILY Littelfuse ly Self Protected S 34 S 321 N P Xxxxx UL Recognized Component Mark Production Site Code DISC SIZE (mm) 34mm CERAMIC SHAPE S: Square VM(AC)RMS 115V to 75V Littelfuse Mark Part Number Production Date Dode (Year and Week) S34S321MP 1148 M:With Isolated Monitored Switch N: Non Isolated Monitored Switch Design P: Lead-Free and RoHS compliant Option Codes
Device Dimension Lead Configuration 41Max 2Max 44.5Max LF 9 S34S321MP 1148 SXXS321MP 129 (Normal Close) 1Min 11.±.5 1Min SXXS321MP 1.4±.2 129 1.2±.3 3*.6±.2 6.±.2.3±.2.5±.2 S2 S3 S1 21.5±.2 S2 S3 S1 3.6±.3 6.±.2 S2 (Normal S3 S1 Close) S2 S3 S1 (Normal open) (Normal open) 2.5±.3 6.5±2.2 Application Example * LED is off when the product is normal(s1,s3 connected), LED is on when the product disconect opens(switch change status; S2,S3 connected as shown by dotted line ). * LED is off when the product is normal(s1,s3 connected), LED is on when the product disconect opens(switch change status; S2,S3 connected as shown by dotted line ). LED R Note: EXAMPLE ONLY - Connection to S2-S3 and S1-S3 depends on customer indication circuit and can vary. To Protected Circuit Note: EXAMPLE ONLY - Connection to S2-S3 and S1-S3 depends on customer indication circuit and can vary. R LED Switch Specification S Switch Voltage DC (Amps) Contact Resistance Max. Insulation Resistance Min. Dialectric Strength.5mA/Minute Switch 12V.1A 7mΩ MΩ 5VAC Disclaimer Notice - Information furnished is believed to be accurate and reliable. However, users should independently evaluate the suitability of and test each product selected for their own applications. Littelfuse products are not designed for, and may not be used in, all applications. Read complete Disclaimer Notice at www.littelfuse.com/disclaimer-electronics.