The testing center of the STC "FGC UES" in Moscow successfully tested a new product of the VVA-a high-speed earthing device as part of the switchgear RUEN-UETM-110. The development of a new earthing device was started by specialists of OGK HVE in connection with a large supply of RUEN for the modernization of power units of a large facility, since the presence of a high-speed earthing device was one of the customer's conditions. In addition, the RUEN produced by UETM is classified as a GIS, and for GIS there are certain requirements for the mandatory use of high-speed earthing devices. In particular, for grounding cable lines, on which it may be difficult to determine the presence of voltage, the use of such earthing devices is mandatory.
“It is more correct to call this device a "ground conductor with switching capacity", Mikhail Karmazin, Deputy Chief Designer of the VVA for disconnectors, head of the design bureau, explains. “Its function is the same as that of a conventional earthing device – to ground de-energized sections of the network to ensure safety during any work. The high-speed earthing device has its own characteristics, which are due to the RUEN itself. Let's imagine an emergency situation in which, for some reason, an attempt is made to ground a section of the network with the voltage not removed. In classical conditions, when we are dealing with stand-alone ORU equipment, such inclusion will lead to a short circuit and damage only the grounding conductor (or the disconnector in which it is built). However, in our case, we are dealing with a gas-filled cell, and the consequences of emergency grounding in the case of using a conventional (slow) earthing device will be fatal for the entire cell. Therefore, a ground conductor with an enabling capacity, unlike a conventional one, is designed so that it is possible to turn it on to an un-energized section of the network (although such an event is an emergency for the network). The contacts of such a grounding conductor, like those of switches, are closed at a high speed, and the contacts themselves have arc-resistant metal-ceramic soldering.
In order to confirm the compliance of the new product with the technical requirements and ensure access to the market of PJSC ROSSETI, the new earthing device as part of the RUEN-UETM-110 was tested for compliance with the requirements of the standards of JSC STC FGC UES.
