TDK has introduced the MT40 series of ThermoFuse varistors, with ordering code B72240M. The series is a new generation of surge protection components (SPC) that use patented overmolding technology and an integrated thermal disconnecting system. The components measure 38.0 x 15.2 x 40.9 mm (L x W x H). The MT40 series provides peak surge current capability of up to 50 kA (8/20 μs pulse) and a short-circuit current rating (SCCR) of up to 200 kA according to UL 1449. The components are recognized as UL 1449 Type 1CA for both AC and DC applications. They support AC voltages from 150 V to 550 V and DC voltages from 200 V to 750 V.
Additional features include a galvanically insulated normally open micro-switch for remote monitoring and an optional visual indicator.
The series operates in temperatures from -40 °C to +85 °C. The varistors are strap-terminated with a thermal disconnecting system and encapsulated in flame-retardant epoxy coating. They are RoHS, REACH, and PFAS compliant. Main applications include PV systems, industrial power supplies, outdoor lighting systems, telecommunication systems, and surge protective devices (SPD).
Main features and benefits listed are:
Strap-terminated varistor with a thermal disconnecting system
Compact size
Flame-retardant epoxy encapsulation
Short circuit current rating (SCCR) up to 200 kA acc. to UL 1449
High peak surge current up to 50 kA
UL 1449-recognized as a type 1CA for both AC and DC applications (file number E321126)
Normally open micro-switch for remote indication/monitoring circuit
Same electrode footprint of PCB for all types
RoHS, REACH, and PFAS compliant
