Type: 3120-N

~ 53 mm
Typ 3120-N von E-T-A: Der thermische Kombi-Schutzschalter Typ 3120-N...-....T1-...

The 3120-N...-...T1-... thermal circuit breaker/switch combination unites overcurrent protection and the function of an ON/OFF switch within a single component. The trip element is a thermal bimetal.
Type 3120-N...-...T1-... is ideally suited for overload protection of motors, pumps, transformers and cables. After tripping, it can reliably, easily and quickly be reset. The positively trip-free mechanism ensures reliable disconnection of the circuit even with the actuator blocked.

Type 3120-N is also available with thermal-magnetic trip (please see data sheet circuit breaker p. 19 ff).

Your benefits:

  • Maximum equipment availability is ensured by overload protection perfectly matched with the loads (prevention of nuisance tripping) and quick resettability
  • Reduced mounting and wiring time
  • Space-saving design
  • Reduced disposition and storage costs
  • Increased overall reliability

Type 3120-N is also available as a switch in accordance IEC/EN 61058 (see data sheet switch only).

Voltage rating
  • AC 240 V, DC 50 V
  • AC 415 V upon request
Current ratings from 0.1 A until 20 A  
(up to 30 A to special order, single pole only)
Number of poles single pole
double pole
Mounting method flange
Terminal design blade terminals
screw terminals
Actuation push button
Auxiliary contacts with auxiliary contacts
without auxiliary contacts
Water splash protection with water splash protection
without water splash protection
Illumination with illumination
without illumination
Typical life single pole
AC 240 V:
0,1...20 A 30 000 operations at 1 x IN, inductive

DC 50 V:
0,1...4 A 30 000 operations at 1 x IN, inductive
4,5...16 A 30 000 operations at 1 x IN, resistive

DC 28 V:
0,1...20 A 30 000 operations at 1 x IN, inductive

double pole
AC 240 V:
0,1...16 A 50 000 operations at 1 x IN, inductive
17...20 A 30 000 operations at 1 x IN, inductive

DC 50 V:
0,1...16 A 50 000 operations at 1 x IN, inductive
17...20 A 10 000 operations at 1 x IN, inductive
Interrupting capacity Icn (IEC/EN 60934)
1, 2-pole: IN 0,1 ... 2 A, UN AC 240 V / DC 50 V, Icn 10 x IN
1-pole: IN 2,5 ... 10 A, UN DC 50 V, Icn 50 A
1-pole: IN 2,5 ... 20 A, UN AC 240 V / DC 28 V, Icn 200 A
2-pole: IN 2,5 ... 20 A, UN DC 50 V, Icn 250 A
2-pole: IN 2,5 ... 20 A, UN AC 240 V / DC 28 V, Icn 300 A
Certificates VDE, UL, CSA, CCC, KC


Order number Description
Y 312 140 01 plug-in connector
Y 304 275 01 water splash cover black
Y 303 862 01 terminal adapter
Y 303 068 01 insulated cover
Y 303 675 01 spacer for -F3/N3...
panel thickness < 2 mm
Y 303 675 02 spacer for -F3/N3...
panel thickness < 4 mm
Y 303 676 01 spacer for -F5/N5...
Y 303 885 31 blanking piece


  • Household, Hobby & Garden Equipment
  • Industrial equipment control
  • Medical technology

Scopes of applications

Medical and laboratory equipment, apparatus and machine construction, professional tools, household and garden appliances, offices machines, audio equipment, machine tools


Datasheet & Explanations

You might be interested in...

Next Generation of 3120 Circuit Breaker/ Switch

The same high quality the 3120 is known for with enhancements the market demanded.

Watch Video


Fuse vs. circuit breaker: How to choose the right device for your application

Is a fuse or circuit breaker best for your design? Here are some pointers to help you decide. Three main factors go into choosing between circuit breakers and fuses: Convenience for the user, cost, and degree of protection. This white paper will give you guidance on what circuit protection device is best for your equipment.

Read White Paper

12 Most Common Mistakes When Specifying Circuit Protection for Equipment

It's only a circuit breaker. Yet there is enough complexity and confusion when it comes to specifying circuit protection that many engineers are designing equipment with too little or too much protection. Under protected circuits leave equipment vulnerable to damaging electrical surges. Over protected circuits add cost and can lead to nuisance tripping. Like Goldilocks and the three bears, the goal is to specify circuit protection that is "just right".

Read White Paper

Virtual Assistant
Quickselect: Products Jobs Support About E-T-A
Call An Expert
Sie haben Fragen, Anregungen oder Wünsche? Wir beraten Sie gerne.