Siemens 3VF5212-2MK47-7KN1 Moulded Case Circuit Breaker Unit

Module Feature

3VF5212-2MK47-7KN1 is a 3-pole moulded case circuit breaker from Siemens 3VF series.

It adopts thermal-magnetic trip element, provides overload long delay protection and instantaneous short-circuit protection. Suitable for power distribution circuits of factories and buildings. It can be equipped with auxiliary contact and shunt release accessories. Widely stocked as maintenance spare for low voltage switchgear cabinet.

Working principle

The bimetallic strip heats and deforms under overload current to trigger the tripping mechanism.

When short-circuit fault occurs, the magnetic component generates instantaneous electromagnetic force to rapidly open the contact, cutting off the fault current and protecting the downstream cables and loads.

Onboard components

Bimetallic thermal trip element, magnetic trip coil, contact assembly, arc extinguishing chamber, operating handle and flame retardant plastic housing.

LED indicators

No built-in status LED, position indication via mechanical handle.

Hardware self‑diagnosis

Manual inspection for contact wear, arc chamber carbon deposition and mechanical operation health. Setting adjustment is completed by front dial.

Programming software

Not applicable, locally adjustable circuit breaker.

Electrical & Process Parameters

Model: 3VF5212-2MK47-7KN1 Brand: Siemens Device type: Moulded case circuit breaker Function: Overload and short circuit protection for low voltage distribution circuit

Mechanical & Structure

Mounting: Panel mounting inside distribution cabinet Protection class: IP40 (front panel) Housing: Flame retardant reinforced plastic

Environmental

Operating temperature: -25℃ ~ +70℃ Storage temperature: -40℃ ~ +85℃ Ambient humidity: 5~95% non‑condensing

Certification: CE Status: Original Siemens electrical spare

Installation

Cut off upstream power supply before replacement.

Install breaker on mounting base, connect incoming and outgoing cables, check trip setting value, test closing, opening and trip function after commissioning.

Interface

Three-phase main circuit terminals, optional auxiliary contact terminals, shunt release terminals.

Diagnostic

Overload trip: Load current exceeds setting, poor heat dissipation. Instantaneous trip: Short circuit fault on load side. Cannot close: Internal mechanical interlock or trip latch stuck.

Product Brief

3VF5212-2MK47-7KN1 breaker, Siemens 3VF 3-pole thermal-magnetic moulded case circuit breaker spare for low voltage power distribution cabinet