Littelfuse SMOV25S Varistor Series - Manual

© 2013 Littelfuse, Inc. 237
Revised: May 8, 2013
Varistor Products
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/smov25s.html for current information.
SMOV25S Varistor Series
Thermally Protected Varistors > SMOV25S Series
SMOV
25S
Series
RoHS
Description
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.
• Recognized to UL
1449 3rd edition.
• Lead-Free and RoHS
compliant.
• Integrated micro-switch for
indication circuitry/design.
Agency Approvals
Applications
• SPD applications
• AC/DC distribution
• IT/Data center
• Power supplier
• Telecommunication
Agency Agency File Number
E320116
SMOV25S Varistor Series
The Littelfuse SMOV 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
3rd edition. 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
simplifies the customers circuit design.
Absolute Maximum Ratings
• For ratings of individual members of a series, see Device Ratings and Specifications chart.
SMOV25S 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 disconnect 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.