Siemens 3RA2120-1KE24-0AP0 SIRIUS Direct Starter, S0

Name: 3RA2120-1KE24-0AP0
Brand: Siemens
SKU: 3RA2120-1KE24-0AP0
Availability: LimitedAvailability
Author: Shop-Floor Sal

Specifications

Identification

3RA2120-1KE24-0AP0 — Identification
Parameter	Value
Product designation	Direct (on-line) starter
Main circuit poles	3
Brand	SIRIUS
Load feeder size	S0
Product design / construction	for standard rail or screw mounting
Circuit-breaker size	S0
Included contactor (type)	3RT2024-2AP00
Included circuit-breaker (type)	3RV2021-1KA20
Included link module (type)	3RA2921-2AA00

Ratings & Performance

3RA2120-1KE24-0AP0 — Ratings & Performance
Parameter	Value
Rated motor power at 400 V	5 500 kW
Rated voltage at AC-3, max.	690 V
Rated motor power at 460/480 V (hp)	7.5 hp
Rated motor power at 575/600 V (hp)	10 hp
Rated current at 480 V	11 A
Rated current at 600 V	10 A
Rated operating frequency	50 ... 60 Hz
Rated impulse withstand voltage (Uimp)	6 kV
Rated insulation voltage Ui (AC, pollution degree 3)	690 V

Protection & Tripping

3RA2120-1KE24-0AP0 — Protection & Tripping
Parameter	Value
Trip class	CLASS 10
Short-circuit protection	Yes
Rated short-circuit current at 400 V (IEC 60947-4-1)	150 000 A
Overload release setting range (current)	9 ... 12.5 A
Overload release type	thermal (bimetallic)
Short-circuit trip type	magnetic
Duty / utilization type (IEC 60947-6-2)	2

Contacts & Control

3RA2120-1KE24-0AP0 — Contacts & Control
Parameter	Value
Rated value	690 V
Rated voltage range at 50 Hz	230 ... 230 V
Control supply voltage type	AC
Auxiliary switch extension	Yes
Switching contact type	electromechanical

Communication

3RA2120-1KE24-0AP0 — Communication
Parameter	Value
AS-Interface protocol support	No

Mechanical & Connection

3RA2120-1KE24-0AP0 — Mechanical & Connection
Parameter	Value
Mounting / fastening method	screw and snap-on mounting onto 35 mm DIN rail
Mounting position	vertical
Width	45 mm
Height	243 mm
Depth	107 mm

Environmental

3RA2120-1KE24-0AP0 — Environmental
Parameter	Value
Operating temperature range	-20 ... +60 °C
Storage temperature range	-50 ... +80 °C
Transport temperature range	-50 ... +80 °C
Shock resistance (IEC 60068-2-27)	6g / 11 ms

Product details

What this SIRIUS direct starter is and what it carries

The Siemens 3RA2120-1KE24-0AP0 is a SIRIUS direct online starter in the size S0 footprint — a factory-assembled combination of a contactor, thermal overload relay, and link module in one package, ready to bolt into a motor branch circuit. It ships with a 3RT2024-2AP00 contactor and a 3RA2921-2AA00 link module, so you get a matched set out of the box — no separate ordering of the contactor and overload.

Trip class, mounting, and the thermal protection story

Spring-loaded terminals on the main current circuit — no screw torque to check, no loosening from vibration — which is a time-saver on the panel build and a reliability win on a machine that shakes. Clearance requirements: 50 mm above, 20 mm forward, 20 mm at the sides, 10 mm below, and zero backward — tight enough that you can stack these starters in a row without a lot of dead air.

Frequently asked questions

What is 3RA2120-1KE24-0AP0's listed depth on this Motor Starters line?

The depth is 107 mm, with a width of 45 mm and a height of 243 mm. It mounts vertically on a 35 mm DIN rail or with screws, and requires 50 mm clearance above, 20 mm forward, 20 mm at the sides, and 10 mm below.

What motor horsepower ratings does this starter cover at common voltages?

The current ratings are 11 A at 480 V and 10 A at 600 V in AC-3 duty.