Metal-Oxide Varistors (MOVs) Thermally Protected Varistors > SMOV 25S Varistor Series

Transcription

1 S25S Varistor Series RoHS Description The Littelfuse S 25S thermally protected varistor is a self-protected device. It consists of a 25mm 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 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. Agency Agency Approval Agency File Number UL1449 E Additional Information Datasheet Resources Samples Features Maximum single surge capability 20 ka, 8/20 waveshape. Nominal Discharge Current Value: 10kA. Intermediate current rating: 50A/150A. -45 C to +75 C operating temperature. Applications Recognized to UL Lead-Free and RoHS compliant. Integrated micro-switch for indication circuitry/design. 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. S25S Varistor Series Units Continous: Steady State Applied Voltage: DC Voltage Range (VM(DC)) 150 to 970 V AC Voltage Range (V M(AC)RMS ) 115 to 750 V Transient: Non-Repetitive Surge Current, 8/20µs Waveform (I TM ) 20,000 A Non-Repetitive Energy Capability, 2ms Waveform (W TM ) 170 to 670 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) 2500 V Isolation Voltage Capability (when the thermal opens) 1500 V Housing Insulation Resistance >1,000 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.

2 Device Ratings & Specifications Maximum Rating (75 C) Specifications (25 C) Part Number AC Volts Continuous DC Volts Energy 2ms Transient Peak Surge Current 8/20μs Nominal Discharge Current (In) Varistor Voltage at 1mA Test Current Maximum Clamping Voltage 8/20μs Typical Capacitance f = 1MHz S25S111MP S25S111NP S25S131MP S25S131NP S25S151MP S25S151NP S25S181MP S25S181NP S25S251MP S25S251NP S25S271MP S25S271NP S25S301MP S25S301NP S25S321MP S25S321NP S25S421MP S25S421NP S25S461MP S25S461NP S25S511MP S25S511NP S25S551MP S25S551NP S25S621MP S25S621NP S25S751MP S25S751NP I V M (AC) V M(DC) W TM TM In Vc I 1 Pulse Min Max PK C (V) (V) (J) (A) (A) (V) (V) (A) (pf) V N(DC) V N(DC) Average power dissipation of transients should not exceed 1.5 watts Same ratings and specifications apply to Non Isolated Monitored Switch alternative design. Replace "M" with "N" in the part number. e.g.: S25S111NP. Refer to Part Number System at the end of this document.

3 Thermal Characteristics Typical time to open circuit under UL 1449 Limited Current Abnormal Overvoltage Test: Peak Current & Energy Derating Curve For applications exceeding 75ºC ambient temperature, the peak surge current and energy ratings must be reduced as shown below. 10 Current (A) 1 Typical 10 A 5 A 2.5 A 0.5 A PERCENT OF RATED VALUE AMBIENT TEMPERATURE (ºC) 1 10 Figure 1 Time (secs) Figure 2 Transient V I Characteristic Curves Maximum Peak Voltage (V) µA µa 1mA 10mA ma 1A 10A A 0A 00A 000A Figure 3 Peak Current

4 Pulse Rating Curve Figure Impulse Duration (secs) Wave Solder Profile Because the S 25S 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 Maximum Wave 240C Maximum Wave 260C TEMPERATURE (ºC) TEMPERATURE (ºC) Figure 5 TIME(MINUTES) Figure 6 TIME(MINUTES) Physical Specifications Environmental Specifications Lead Material Soldering Characteristics Insulating Material Device Labeling Tin plated Solderability per MIL-STD-202, Method 208 Cured, flame retardant epoxy polymer meets UL94V-0 requirements Marked with LF, voltage, UL logos, and date code Operating/Storage Temp. Passive Aging Humidity Aging Thermal Shock -45 C to +75 C +75 C, 0 hours -/+10% typical voltage change +75 C, 85%R.H., 0 hours -/+10% typical voltage change +75 C to -40 C 5 times -/+10% typical voltage change Solvent Resistance MIL-STD-202, Method 215 Moisture Sensitivity Level 1, J-STD-020

5 Product Dimensions Lead Configuration 31Max 16.5Max 9Min 36Max 10Min 1148 LF9 SXXS321MP 1.3± ± ±0.2 3*0.6± ± ±0.5 LF 9 S25S321MP 13.4±0.2 S2 S3 S1 0.5±0.2 Thermal 2± ±0.2 SXXS321MP 1209 LF9 S2 S1 S3 ON S1 (Normal Close) Common S2 S3 S1 (Normal open) Thermal S1 ON (Normal Close) S3 Common (Normal open) 2.5± ±1.2 Application Example S2 S3 S1 Thermal * 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 ). S1 ON R LED Thermal * 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 ). S1 ON S3 Common Note: EXAMPLE ONLY - Connection to S2-S3 and S1-S3 depends on customer indication circuit and can vary. LED R S3 Common Note: EXAMPLE ONLY - Connection to S2-S3 and S1-S3 depends on customer indication circuit and can vary. To Protected Circuit Switch Specification S Switch Voltage DC Current (Amps) Contact Resistance Max. Insulation Resistance Min. Dialectric Strength 0.5mA/Minute Switch 12V 0.1A 70mΩ MΩ 500VAC

6 Part Numbering System Part Marking System DEVICE FAMILY Littelfuse Thermally Self Protected DISC SIZE (mm) 25mm CERAMIC SHAPE S: Square VM(AC)RMS 115V to 750V S 25 S 321 N P M:With Isolated Monitored Switch N: Non Isolated Monitored Switch Design P: Lead-Free and RoHS compliant Option Codes Xxxxx UL Recognized Component Mark Production Site Code Littelfuse Mark Part Number Production Date Dode (Year and Week) LF9 S25S321MP 1148 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