Electricity + Control February 2019

Conclusion In an ever-changing world where the overall goal is to become less fossil fuel depend- ent and more energy efficient not only do the devices we use on a daily basis need to change, but also the power grid that sup- plies these devices. Small improvements in efficiency, no matter how minute, can add up to significant savings when scaled up to world-wide proportions.

Aaron Rost is a con- tracts and proposals engineer at Trafo Power Solutions. He holds a Bachelor of Technolo- gy Degree in Electrical Engineering, with expe- rience in various fields in- cluding variable speed drives, partial discharge and transformer testing. Rost is passionate about cutting edge technolo- gy that allows the indus- try to be eco-friendly.

Safety and efficiency in ReStart solutions

ACDC Dynamics has introduced the new version of Gewiss protec- tion devices, the ReStart range of advanced residual current devic- es that provide for safety while ensuring continuous efficiency in the electrical system. They can be used in residential and industrial applications. The new concept of safety from Gewiss takes a dual form. Re- Start solutions ensure service continuity in case of untimely trip- ping, only resetting the residual current circuit breaker once the ReStart device has ensured that there are no faults in the system. ReStart Autotest solutions perform regular automatic tests on the residual current device, without cutting power to the system. The key benefit of ReStart is that it ensures the system is auto- matically reset if the circuit breaker trips, preventing disruption and possible damage to the system and connected applications. In ad- dition, the device will restore power to the system only once it has checked the system for faults. This eliminates the risk of electric shock for anyone working on the system. A further benefit of the new version of the ReStart device is that it is even more compact than previous versions. The solution for single-phase systems occupies only one DIN module, for the widest possible options for installation within the enclosure. The new version is also faster: it can check the system and reset the circuit breaker in just 10 seconds. ReStart Autotest is reportedly the only device on the market that can carry out periodic safety testing on the residual current, without cutting power to the system. This function is enabled by

Gewiss’ patented bypass contacts and eliminates any disadvan- tages relating to interruptions in the power supply or voltage dips. ReStart Autotest performs a test every 28 days, promoting safety and continuous efficiency for the protection device. It also provides for maximum residual current protection efficiency, even over a long period of time. It is available in 2P and 4P versions for single-phase and three-phase distribution systems. Both the ReStart and ReStart Autotest devices are available in PRO and TOP versions. The PRO versions offer continuous control and protection of the system. When the circuit breaker trips, these devices check the state of insulation of the system for as long as it takes until the fault has been resolved, before resetting the system safely. The TOP versions allow for the timing and modes according to which the circuit breaker is automatically reset to be adjusted, so the operator can set the number of attempts and the automatic reset time delay. The advanced features of ReStart and ReStart Autotest make the devices suitable for use in a range of different installations in the residential and industrial sectors and in ‘special’ applications. They are also ideal for unsupervised systems, to ensure service continuity and reduce maintenance-related issues. Reliability and service con- tinuity can be guaranteed for systems installed in remote locations, for example, with no need for expensive technical operations to re- solve false alarms, or where a temporary blackout occurs. Enquiries: ACDC Dynamics.Tel. +27 (0)10 202 3300 or email info@acdc.co.za

Electricity + Control

FEBRUARY 2019

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