The series of Tmax moulded-case circuit-breakers - complying with the IEC 60947-2 Standard - is divided into seven basic sizes, with an application range from 1 A to 1600 A and breaking capacities from 16 kA to 200 kA (at 380/415 V AC).
For protection of alternating current networks, the following are available:
– T1B 1p circuit-breaker, equipped with TMF thermomagnetic trip units with fixed thermal and
magnetic threshold (I3 = 10 x In);
– T1, T2, T3 and T4 (up to 50 A) circuit-breakers equipped with TMD thermomagnetic trip units
with adjustable thermal threshold (I1 = 0.7…1 x In) and fixed magnetic threshold (I3 = 10 x In);
– T2, T3 and T5 circuit-breakers, fitted with TMG trip units for long cables and generator protection with adjustable thermal threshold (I1 = 0.7…1 x In) and fixed magnetic threshold (I3 = 3 x In) for T2 and T3 and adjustable magnetic threshold (I3 = 2.5…5 x In) for T5;
– T4, T5 and T6 circuit-breakers with TMA thermomagnetic trip units with adjustable thermal threshold
(I1 = 0.7…1 x In) and adjustable magnetic threshold (I3 = 5…10 x In);
– T2 with PR221DS electronic trip unit;
– T4, T5 and T6 with PR221DS, PR222DS/P, PR222DS/PD and PR223DS electronic trip units;
– the T7 circuit-breaker, which completes the Tmax family up to 1600 A, fitted with PR231/P, PR232/P, PR331/P and PR332/P electronic trip units.
The T7 circuit-breaker is available in the two versions:
with manual operating mechanism or motorizable with stored energy operating mechanism(*).
The field of application in alternating current of the Tmax series varies from 1 A to 1600 A with voltages up to 690 V. The Tmax T1, T2, T3, T4, T5 and T6 circuit-breakers equipped with TMF, TMD and TMA thermomagnetic trip units can also be used in direct current plants, with a range of application from 1 A to 800 A and a minimum operating voltage of 24 V DC, according to the appropriate connection diagrams.
The three-pole T2, T3 and T4 circuit-breakers can also be fitted with MF and MA adjustable magnetic only trip units, both for applications in alternating current and in direct current, in particular for motor protection (see page 2/45 and following).
For all the circuit-breakers in the series, fitted with thermomagnetic and electronic trip units, the
single-phase trip current is defined .