Almost 90 % of all systems are operated at 24 Vdc. For the availability and operational reliability of such systems, reliable and selective protection of the 24 V control voltage level is a mandatory. Ultimately, a permanent overload can damage wire insulation and may cause a long-term shutdown. It is also essential that the protection concept can be flexibly adapted to the respective conditions and be optimally integrated into the overall system. In the final application, various numbers of protection channels are required and, if needed, individual channels can be subsequently added. If a detailed status of individual loads is to be monitored remotely, currently available products are providing limited features only. Let us show you how the modular 24 V circuit breaker system, EasyB from BLOCK, demonstrates how this can be done differently.
◼︎ Optionally with current limiting, thermomagnetic characteristic or thermomagnetic fast tripping characteristic
The BLOCK electronic circuit breakers are designed for a variety of requirements in machines and devices. Available are three different tripping options. Circuit breakers with thermomagnetic, fast-tripping and current-limiting characteristics represent a cost-effective alternative to conventional circuit breakers. The wide selection of shutdown characteristics guarantee reliable tripping for any application, including at high line impedances.
The requirements regarding the tripping behavior of electronic circuit breakers in machines and systems are manifold: loads with high starting and inrush currents such as drives and contactors, for instance, require different tripping characteristics to sensors and controls which react sensitively to system voltage drops. BLOCK is expanding its EasyB model range to include a new and fast tripping characteristic so that it can provide the optimum solution to the user for the relevant application in all cases. This means that safe tripping following a short circuit within 2 ms and the switching on of capacitive loads with up to 40 mF is no problem for EasyB.
Electronic circuit breakers are designed for the special behavior of switched mode power supplies and the DC 24 V loads they supply. They distribute the load current to several circuits and protect loads and wiring even for long cable lengths and small cross-sections.
For any application
Circuit breakers with thermomagnetic, fast-tripping and current-limiting characteristics represent a cost-effective alternative to conventional circuit breakers. The wide selection of shutdown characteristics guarantee reliable tripping for any application, including at high line impedances.
For inductive loads
Modules with thermomagnetic tripping characteristics show the same tripping behavior as conventional circuit breakers. In operation, these modules can accommodate high starting or inrush currents for loads over short periods. Ideal for inductive loads – such as contactors, drives and valves.
For sensitive loads
The fast-tripping alternative to standard characteristics, particularly at rated currents <6 A. These universal modules can be relied on to trip in less than 2 ms in the event of a short circuit, thereby limiting the potential for system voltage drops. Ideal for sensitive loads such as control systems and sensors.
For capacitive loads
These modules limit the overcurrent for any circuit to a maximum of 1.7 times the rated current set. In the event of a persistent overcurrent, only the defective circuit is shut down on a selective basis. Any voltage drop in circuits not affected is prevented with a high degree of reliability. Ideal for capacitive loads > 70 mF, which can be charged at constant current without any problems at the time of switching on.
The individual channels can exchange important information and forward this to a connected communication module. The communication module provides this information to a higher-level controller. Information such as the current channel status, including the current presently flowing and the input voltage applied, is therefore easy and quick to access.
All of the EasyB series is UL-certified in accordance with UL 508 and UL 2367. In addition, both the channels with current-limiting characteristics and the new versions with fast-tripping characteristics benefit from NEC Class 2 approval for the 1 to 4 A current range. This approval makes it possible to create up to four circuits with limited power of 100 VA. If a system or machine is to be sold on the American market, its design must be UL-compliant and it also requires UL approval. With the circuit breakers benefiting from NEC Class 2 approval, loads and lines can be used without UL approval. The system will still meet UL requirements. Whether used in mechanical and systems engineering, wind power applications or transport – the circuit breakers are really well protected against impact and vibrations and benefit from DNV GL certification accordingly. The internal fuses, all individually adapted to the rated current of 1 to 10 A, are compliant with both IEC 60127-4/2 and UL 248-14. The system also meets the line protection requirements associated with EN 60204-1.
The circuit breaker system offers users added value that goes beyond the core functionality of line protection. Scalable functionality and equipment levels, from the low-cost version with basic functionality and trip characteristics tailored to the individual application through to the intelligent power distribution and protection system with field bus connection to the higher-level control system via various bus couplers. Messages regarding operating and error statuses for each channel are therefore readily and quickly available. It is also possible to set parameters for any number of output channels, and these can be actively switched on or off or even reset. There is the option as well to set the tripping current via the communication bus. In this type of application, the IO-Link interface in particular can really highlight the advantages of a low-cost communications connection without a field bus. So EasyB meets all the requirements for designing Industry 4.0-compatible systems in terms of condition monitoring and predictive maintenance.