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Electronic Circuit Breakers (ECBs)

A high switch-on capacity is combined with an electronic relay.
WAGO’s space-saving ECBs come into play when the focus is on both safety and a superior price–performance ratio.

WAGO’s ECBs have a lot to offer:

  • They reliably protect against overload and short circuits.
  • They also enable the activation of high-capacitance loads of 50,000 μF and more, without increasing the rated current setting.
  • One-, two-, four- and eight-channel models and current ratings of 0.5 to 12 A offer you the flexibility you need for setting the rated current to suit your individual application.
  • With a maximum width of 45 mm (1.772 inches), these ECBs feature high channel density to save space in the control cabinet.
  • Some devices are also available with active current limitation, preventing the power supply unit from overloading during a short circuit.

Product Overview

Discover Our ECBs

Single-Channel Electronic Circuit Breakers (ECBs)

The new modules are just 6 mm (0.236 inch) wide, making them the slimmest ECBs currently available on the market. They are approximately 66 % smaller than miniature circuit breakers, saving even more space, particularly when used in control cabinets. These ECBs allow high-capacitance loads greater than 50,000 μF to be switched on – helping you reduce false tripping due to inrush currents.

The Benefits for You:

  • 24 VDC; six versions available for rated currents of 1 to 8 A
  • Devices color coded according to rated current
  • An extremely slimline design
  • Switch-on capacity: > 50,000 µF
  • Wide surrounding air temperature range: −25 … +70 °C (−13 … +158 °F)
  • Resetting, on/off switching directly on the module or remotely via digital input signal
  • Triggered signal output – can also be commoned as a group signal for up to 30 devices
  • Approvals: CE, UL 61010, UL 2367

2-, 4- and 8-Channel ECBs

WAGO’s space-saving ECBs provide reliable protection with a superior price–performance ratio. They offer both outstanding features and reliable protection against overload and short circuits. With a maximum width of 45 mm (1.772 inches), these ECBs feature high channel density to save space in the control cabinet.

The Benefits for You:

  • Two-, four- and eight-channel protective switch with currents adjustable from 0.5 to 12 A
  • High switch-on capacity: > 50,000 µF
  • Communication capability: remote monitoring and reset
  • Optional active current limitation
  • Approvals: CE, UL 60950, UL 2367, GL

The Benefits of WAGO’s ECBs for You

Why Secondary-Side Fuse Protection?

On the secondary side, switched-mode power supplies provide DC voltage to control circuit loads (e.g., controllers, operating panels, displays and auxiliary relays). These control circuits also call for wiring protection and if the load has no protective unit of its own, device protection as well. Furthermore, Machinery Directive EN 60204 requires detecting hazardous ground faults in control circuits and switching them off within five seconds.

The overcurrent protection in primary switched-mode power supplies reacts very quickly to overcurrents on the output side. Selective protection of individual current paths in the secondary circuit via fuses or conventional circuit breakers is often ineffective if the power supply cannot deliver a brief overcurrent.


What Types of Fuse Protection Are There?


Possible applications:

  • Low-voltage, high-power and DP fuses
  • High overcurrents required for fast tripping


  • In the example: ten-fold overcurrent (related to fuse nominal current): Tripping within a range of 30 ms (best case) or 200 ms (worst case)
  • Only two-fold overcurrent: tripping within a range of 2 s (best case) or >100 s (worst case).

Thermal and Magnetic

Possible applications:

  • Found in circuit breakers or motor protection switches
  • High overcurrents required for fast tripping


  • In the example: three- to five-fold overcurrent for B-characteristic and AC operation, additional safety factor: 1.2 or 1.5
  • Thus, in the worst case scenario, a tripping current of 7.5 times the nominal current is necessary.



Possible applications:

  • Precision setting options
  • Reaction within a short time – even with low overcurrents
  • Protection of long cable runs and small cross sections possible

ECBs ensure reliable protection, even at low overcurrents and with long cable lengths.


How Does an ECB Function?

The ECB checks whether the output current is greater than the nominal current. As soon as the output current exceeds the nominal current, the output is electronically switched off by a semiconductor switch. Trip time depends on the magnitude of the overcurrent. The measurement of the output current, the processing and calculation of the tripping time and the actuation of the semiconductor switch are performed by a microprocessor that monitors one or more output channels. The corresponding tripping times can be found in the graph on the right.


ECB Advantages

  • Switch off secondary-side overcurrents and short circuits – even with long cable runs and small conductor cross sections – with precision, speed and repeatability
  • Selectivity, especially with ECBs with active current limitation
  • Remote operation via digital input and output
  • Fast and reliable communication via IO-Link protocol, signal contact, potential-free signal or Manchester protocol
  • Advantageous installation size and width, for example, eight output channels in just 42 mm (1.653 inch), which saves more than 70 % of installation space compared to miniature circuit breakers
  • Nominal current assignable for each channel
  • Satisfy EN 60204-1 requirements for dependably switching off ground faults after five seconds

Recommended Reading

Compatible with Our ECBs

Efficient Power Supplies

Constant supply voltage at any time − worldwide, in the widest range of applications. That’s what makes WAGO’s power supplies so successful!