In the case of direct current, the danger of possible stray currents must be prevented by the direct connection of the
of the return conductors with the water ground must be prevented. Stray currents would buildings,
buildings, bridges and other metallic (electrically conductive) equipment and plant components through
damage due to corrosion. Dangers also arise from impermissibly high
touch voltages. One of the measures for protecting people from impermissible
voltages is the temporary short-circuit, which is used in various grounding systems.
according to DIN EN 50122-1 (VDE 0115 Part 3).
The WITT EscS 6 (EKS8) is a self-resetting earthing short-circuiter according to DIN
VDE 0115 part 300 and part 320. Can be parameterized and used for monitoring
of voltage differences between return conductor and water earth. The combination
of antiparallel thyristors and a power contactor guarantees a low switching time and a high
low switching time, as well as a high current carrying capacity.
This earthing short-circuiter has a particularly compact design.
When the entered voltage curve is exceeded, the earth short-circuiter responds
i.e. after the switch-on criteria have been met, the thyristors are triggered simultaneously and the contactor is switched.
the contactor is switched. The thyristors switch in some microseconds, the contactor has
a closing time of approx. 90 ms. With the ignition of the thyristors the voltage collapses to a few volts.
to a few volts. The thyristors remain fired until the contactor closes
has been detected by the position of the auxiliary contacts of the contactor. After that the
thyristors are cleared. Thus the contactor takes over the load.