Littelfuse TCMOV & SMOV Series Thermally Protected Varistors

TCMOV Series features 34mm² format varistors that combine high maximum surge capability (50kA) with an integrated thermally active element. The TCMOV Series offers a short circuit current rating of 200kA. In the event of overheating due to abnormal overvoltage, the TCMOV Varistors safely disconnects from the circuit. A built-in micro-switch triggered by a mechanical slide indicates when a circuit is completely isolated from the primary circuit.

Features

• 34mm² format varistors with an integral thermal disconnect system designed to open in the event of overheating due to abnormal overvoltage conditions.
• Provides high peak surge current rating (up to 50kA)
• Compact design of MOV with a micro-switch
• Micro-switch can be used to indicate when the MOV is disconnected from the circuit
• Can be wave soldered without any need for special or expensive assembly processes

• Maximum single surge capability up to 50kA, 8/20 wave shape
• Nominal Discharge Current Value(In): 20kA
• Short Circuit Current Rating: 200kA

Datasheet
Application Note

SMOV Series varistors safely disconnect from the circuit in a sustained over-voltage, intermediate current condition as defined by UL1449 (3rd edition). The integrated thermal element is positioned close to the MOV body to allow for a quick thermal response. The varistors offer high peak surge current handling and energy absorption capabilities with an operating voltage range compatible with common AC line voltage (115VAC to 750VAC). A separate micro-switch indicates when the MOV has been disconnected from the circuit. This separate switch isolates the monitoring circuitry from the primary circuit to ensure indicator circuit safety and simplify the user's circuit design.

Features

• 25mm²- or 34mm²- varistor with an integrated thermal disconnect designed to open in the event of overheating due to abnormal overvoltage as outlined in the 3rd edition of UL1449
• Standard operating voltage range compatible with common AC line voltage (115VAC to 750VAC)
• Provides high peak surge current rating (up to 40kA)

Specifications

• Maximum single surge capability up to 40kA, 8/20 wave shape
• Nominal Discharge Current Value(In): 10kA (SMOV25) and 20kA (SMOV34)
• Intermediate current: 50A/150A