Product Overview
787-3861: Next Generation WAGO Single-Channel Electronic Circuit Breakers
WAGOs next generation 24 VDC, 1-channel ECBs improve operations and offer significant cost savings for customers. New in the 787-3861 family is the ability to configure the S2 output on ALL variants and to report 7 different states including triggered or manually switched off along with early load warnings. These devices no longer have a hard to open cover to access the manual reset wheel, offering an indented button to be operated with a tool. On adjustable units, the current limit can be set via discrete setting wheel instead of a sequence of inputs through the manual input wheel, making it much easier to set and identify current settings.
Advantages:
- Six fixed and two adjustable rated current versions from 0.5 A to 8 A
- LED status indicators to identify device status
- 6mm slimline design
- Easy jumpering to 857 and 2857 series devices with same terminal layout
- High switching capacity: > 50,000 μF for non-NEC Class 2 devices
- S1 Input and Configurable S2 Output for easy remote monitoring and control
- Approvals: CE, UL 61010, UL 2367, and UL 1310 NEC Class 2 Versions
Next Generation 4- and 8-Channel ECBs
WAGO’s Next Generation Multi-Channel ECB offering improves channel density and offers even higher current circuit protection. Each configuration takes up just 32 mm on the DIN Rail. 1 to 10 A circuit protection per channel with the option to bind two channels together where 16 A circuit protection can be achieved.
Advantages:
- High switch-on capacity: > 50,000 µF
- Up to 16 A Current Protection
- Group messaging input and output signals for remote control and monitoring
- Approvals: CE, UL 61010-2-201, UL 2367
2-, 4- and 8-Channel ECBs
WAGO’s space-saving ECBs come in two, four, or eight-channel protective switches with currents adjustable from 0.5 to 12 A, providing reliable protection with a superior price/performance ratio. They offer 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.
Advantages:
- High switch-on capacity: > 50,000 µF
- Communication capability: remote monitoring and reset
- Optional active current limitation
- Approvals: CE, UL 60950, UL 2367, GL
787-2861: Single-Channel Electronic Circuit Breakers (ECBs)
These 24 VDC modules are just 6 mm (0.236 inch) wide, making them the slimmest ECBs currently available. They are approximately 66% smaller than miniature circuit breakers, saving even more space, particularly when used in control cabinets. These ECBs enable high-capacity loads greater than 50,000 µF to be switched on – helping you reduce false tripping due to inrush currents.
Advantages:
- Seven versions available for rated currents of 0.5 A to 8 A
- Color coded according to nominal current
- Wide surrounding air temperature range: −25 … +70°C (−13 … +158°F)
- Powering on/off and resetting directly on the module or remotely via digital input signal
- Triggered signal output can be combined as a group signal for up to 30 devices
- Approvals: CE, UL 61010, UL 2367
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?
Thermal
Possible applications:
- Low-voltage, high-power and DP fuses
- High overcurrents required for fast tripping
Explanation:
- 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
Explanation:
- 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.
Electronic
Possible applications:
- Precision setting options
- Reaction within a short time – even with low overcurrents
- Protection of long cable runs and small cross sections possible
Explanation:
- ECBs ensure reliable protection, even at low overcurrents and with long cable lengths.
How Does and 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
Technical Support-Interface
