Thermal-Magnetic Trip Unit; Thermal-Magnetic Trip Unit (Tmtu); Application Cases And Trip Unit Types - Siemens Sentron 3VA Manual

2.6

Thermal-magnetic trip unit

2.6.1

Thermal-magnetic trip unit (TMTU)

A thermal-magnetic trip unit consists of a thermal trip unit for protecting against overload,
and a magnetic trip unit for protecting against short circuits. Both trip units are series-
connected. Thermal-magnetic trip units are available with Fixed-Thermal-Fixed-Magnetic
(FTFM) or Fixed-Thermal-Adjustable-Magnetic (FTAM) settings.
2.6.2

Application cases and trip unit types

The table below illustrates the applications for which different types of thermal-magnetic trip
units can be used:
3VA molded case circuit breakers with UL and IEC certification
Manual, 01/2019, L1V30435333-01
Description
2.6 Thermal-magnetic trip unit
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