3RA1 fuseless load feeders

Note:

The 3RA1 fuseless load feeders, including sizes S00, S0 and S2, can be found

• in the Catalog Add-On IC 10 AO · 2014 in the DVD box IC 01
• in the Catalog Add-On IC 10 AO · 2014 at the Information and Download Center
• in the interactive catalog CA 01
• in the Industry Mall

3RA1 fuseless load feeders consist of the 3RV1 motor starter protector and the 3RT1 contactor. The motor starter protectors and contactor are electrically and mechanically connected using pre-assembled assembly kits (link modules, wiring kits and standard mounting rail or busbar adapters).

As the 3RA1 fuseless load feeders are constructed from 3RV1 motor starter protectors and 3RT1 contactors, the same accessories can be used for the 3RA1 fuseless load feeders as for these motor starter protectors and contactors.

Pre-assembled assembly kits are available as accessories for the power spectrum up to 45 kW. The desired fuseless load feeder can thus be assembled quickly and economically by the customer. A time saving is also achieved in connection with switchgear acceptances, as – unlike with conventional wiring systems – there is no need to rectify possible wiring errors.

The 3RV1 motor starter protector is responsible for overload and short-circuit protection in the fuseless load feeder. Back-up protective devices, such as melting fuses or limiters, are superfluous here, as the motor starter protector is capable of withstanding short circuits of up to 50 or 100 kA at 400 V.

The 3RT1 contactor is particularly suitable for extremely complex switching tasks requiring durable components.

The permissible ambient temperature is 60 °C with side-by-side-mounting and without derating (70 °C possible subject to certain restrictions).

3RA1 fuseless load feeders are available for motors up to 45 kW at AC-3 and 400 V (grounded network) and setting ranges from 0.14 A to 100 A.

Only size S3 of the 3RA1 fuseless load feeders are covered in IC 10. 3RA2 fuseless load feeders are available for sizes S00 and S0.

3RA1 load feeder sizes S2 and S3 can be ordered preassembled only as direct-on-line starters in size S2. The direct-on-line starter size S3 and the reversing starter sizes S2 and S3 are available only for self-assembly.

The SENTRON 3VL circuit breakers and the SIRIUS 3RT contactors can be used for fuseless load feeders > 100 A. The corresponding distances from grounded or live parts, as detailed in the technical specifications, must be observed.

More information and assignment tables for self-assembly combinations for 400 V, 440 V, 480 V, 500 V, 550 V and 690 V can be found in the configuration manual "SIRIUS Configuration: Selection Data for Fuseless Load Feeders”:
https://support.industry.siemens.com/cs/ww/en/view/40625241

Operating conditions

3RA1 fuseless load feeders are climate-proof. They are intended for use in enclosed rooms in which no severe operating conditions (such as dust, caustic vapors, hazardous gases) prevail. Suitable covers must be provided for installation in dusty and damp locations.

Overload tripping times

All 3RA1 fuseless load feeders described here are designed for normal starting, in other words for overload tripping times of less than 10 s (CLASS 10). At rated-load operating temperature the tripping times are shorter, depending on the particular equipment and the setting range. The exact values can be derived from the tripping characteristics of the motor starter protectors.

Types of coordination

EN 60947-4-1 (VDE 0660 Part 102) and IEC 60947-4-1 make a distinction between two different types of coordination, which are referred to as type of coordination "1" and type of coordination "2". Any short circuits that occur are cleared safely by both types of coordination. The only differences concern the extent of the damage caused to the device by a short circuit.

• Type of coordination "1"

The fuseless load feeder may be non-operational after a short circuit has been cleared. Damage to the contactor or to the overload release is permissible.

• Type of coordination "2"

There must be no damage to the overload release or to any other components after a short circuit has been cleared. The load feeder can resume operation without needing to be renewed. At most, welding of the contactor contacts is permissible if they can be disconnected easily without any significant deformation.

The types of coordination are indicated in the corresponding tables by the symbols shown on orange backgrounds.

Connection method

The load feeders 3RA1 are offered with screw-type connection technology.

Direct-on-line starting • For standard rail mounting • Size S00 and S0

This graphical overview is shown without small mounting parts (screws etc.).

This graphical overview is shown without small mounting parts (screws etc.).

This graphical overview is shown without small mounting parts (screws etc.).

Direct-on-line starting • For standard rail mounting • Size S2 and S3

This graphical overview is shown without small mounting parts (screws etc.).

This graphical overview is shown without small mounting parts (screws etc.).

Direct-on-line starting • For 40 mm and 60 mm busbar systems • Size S00 and S0

This graphical overview is shown without small mounting parts (screws etc.).

This graphical overview is shown without small mounting parts (screws etc.).

Direct-on-line starting • For 40 mm and 60 mm busbar systems • Size S0 and S2

This graphical overview is shown without small mounting parts (screws etc.).

This graphical overview is shown without small mounting parts (screws etc.).

Reversing duty • For standard rail mounting • Size S00 and S0

This graphical overview is shown without small mounting parts (screws etc.).

This graphical overview is shown without small mounting parts (screws etc.).

Reversing duty • For standard rail mounting • Size S0

This graphical overview is shown without small mounting parts (screws etc.).

Reversing duty • For standard rail mounting • Size S2

This graphical overview is shown without small mounting parts (screws etc.).

Reversing duty • for standard rail mounting • size S3

This graphical overview is shown without small mounting parts (screws etc.).

Reversing duty • for 40 mm and 60 mm busbar systems • size S00 and S0

This graphical overview is shown without small mounting parts (screws etc.).

Reversing duty • for 60 mm busbar systems • size S2

This graphical overview is shown without small mounting parts (screws etc.).