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TMOV25S/34S Thermal Varistor


The Littelfuse varistor series for surge protection applications is now UL1449 3rd Edition recognized


Littelfuse TMOV25S/34S Thermal VaristorThe Littelfuse TMOV® 25S and TMOV34S Varistor Series are specifically designed for applications that must meet the requirements of the Limited Current, Abnormal Overvoltage test in the UL1449 (3rd edition) Surge Protection Device (SPD) standard. The TMOV 25S and TMOV 34S Series meet the surge suppressor component recognition requirements of UL1449 for both cord-connected and permanently connected SPD end products in a single integrated package. A patented, thermally-responsive element within the body of the varistor will open the device in case of overheating, due to abnormal overvoltages.

The varistors offer high surge current ratings up to 20 kA for TMOV 25S and 40 kA for TMOV 34S. The thermally protected varistors consist of a 25 or 34 mm²-format varistor element (MOV) with an integral thermally activated element. This element is designed to open in the event of overheating due to abnormal overvoltage, limited current conditions. A number of devices include a "monitor" lead that may be connected to signaling circuitry to indicate if the MOV has been disconnected from the circuit. TMOV 34S Series and TMOV 25S varistor series devices offer quick thermal response, due to the close proximity of the integrated thermal element to the MOV body. The integrated configuration also offers lower inductance than most discrete solutions, which helps ensure faster clamping response to overvoltage transients. Datasheet

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Digi-Key P/N Manufacturer P/N Description Varistor Voltage
F5320-ND TMOV25SP115M TMOV VARISTOR PB FREE 25S 198 V
F5321-ND TMOV25SP130M TMOV VARISTOR PB FREE 25S 226 V
F5322-ND TMOV25SP140M TMOV VARISTOR PB FREE 25S 240 V
F5323-ND TMOV25SP150M TMOV VARISTOR PB FREE 25S 264 V
F5324-ND TMOV25SP175M TMOV VARISTOR PB FREE 25S 297 V
F5325-ND TMOV25SP230M TMOV VARISTOR PB FREE 25S 396 V
F5326-ND TMOV25SP250M TMOV VARISTOR PB FREE 25S 429 V
F5327-ND TMOV25SP275M TMOV VARISTOR PB FREE 25S 473 V
F5328-ND TMOV25SP300M TMOV VARISTOR PB FREE 25S 517 V
F5329-ND TMOV25SP320M TMOV VARISTOR PB FREE 25S 561 V
F5330-ND TMOV25SP385M TMOV VARISTOR PB FREE 25S 682 V
F5331-ND TMOV25SP420M TMOV VARISTOR PB FREE 25S 748 V
F5332-ND TMOV25SP440M TMOV VARISTOR PB FREE 25S 787 V
F5333-ND TMOV25SP550M TMOV VARISTOR PB FREE 25S 1001 V
F5334-ND TMOV25SP625M TMOV VARISTOR PB FREE 25S 1100 V
F5335-ND TMOV25SP750M TMOV VARISTOR PB FREE 25S 1320 V
F5336-ND TMOV34S151MP VARISTOR THERMAL 150V 40KA 34MM 268 V
F5337-ND TMOV34S271MP VARISTOR THERMAL 275V 40KA 34MM 473 V