Standards

IEC/EN 60947‑1,
IEC/EN 60947‑4‑1,
IEC/EN 60947‑5‑1 (auxiliary switches)

The 3TF2 miniature contactors are climate-proof, and are finger-safe according to IEC 60529 with screw terminals.

Connection method

The miniature contactors are available in versions with screw terminals, 6.3 mm plug-in terminals and solder pin connections for soldering to printed circuit boards.

Ratings of three-phase motors

The quoted rating (in kW) refers to the output power on the motor shaft (according to the nameplate).

The power rating specifications of the contactors in kW are guide values for 4-pole standard motors at 50 Hz and specified voltage (e.g. 400 V AC). The actual starting and rated data of the motor to be switched must be considered when selecting the units.

AC and DC operation

Surge suppression

RC elements, varistors, diodes or diode assemblies (combination of a diode and a Zener diode for short break times) can be plugged onto all 3TF2 miniature contactors and auxiliary switch blocks with screw terminals from the front in order to dampen opening surges in the coil; see "Accessories and Spare Parts" в†’ "for 3TF, 3TK, 3TC Contactors and 3TH Contactor Relays and Miniature Contactor Relays" в†’ "Accessories for 3TF, 3TG, 3TK Miniature Contactors".

Note:

The OFF-delay times of the NO contacts and the ON-delay times of the NC contacts increase if the contactor coils are attenuated against voltage peaks (suppression diode 6x to 10x; diode assembly 2x to 6x; varistor +2 to 5 ms).

Auxiliary switches

All 3TF2 miniature contactors have an integrated auxiliary contact, either 1 NO or 1 NC.

The miniature contactors with screw terminals can be extended to include snap-on auxiliary switch blocks. They are also available with pre-mounted auxiliary switch blocks.

The miniature contactors with screw terminals with an NO contact (ID 10 according to EN 50012) can be expanded into miniature contactors with 2, 4 and 5 auxiliary contacts according to EN 50012 using auxiliary switch blocks. The identification numbers 11, 22, 23 and 32 on the coded auxiliary switch blocks apply to the complete miniature contactors (see graphic). These auxiliary switch blocks cannot be combined with miniature contactors with identification number 01.

All miniature contactors with screw terminals, identification number 10 or 01, can be expanded to miniature contactors with 3 or 5 auxiliary contacts according to EN 50005 using auxiliary switch blocks 40, 31, 22, 20, 11 and 02. The identification numbers on the auxiliary switch blocks only apply to the attached auxiliary switches.

3TF2 miniature contactors according to EN 50012 or EN 50005

For accessories for miniature contactors, see "Accessories and Spare Parts" в†’ "for 3TF, 3TK, 3TC Contactors and 3TH Contactor Relays and Miniature Contactor Relays" в†’ "Accessories for 3TF, 3TG, 3TK Miniature Contactors".