APTP Articles

Switchgear Incorporates New Technology for Positive Electrical Contact Status Identification

Traditionally with fixed pattern switchgear, the operator views a remotely driven MIMIC representation located on the switchgear front cover depicting the status of the switching contacts. Improving this, is the latest GELPAG fixed pattern solid dielectric MSS switchgear, which allows operators to look inside the epoxy encapsulated switch block to positively view the switching contacts moving into their closed, isolated or earthed positions. 

The new GELPAG MSS fixed pattern switchgear delivers what has been previously un-achievable within the traditional indoor MV fixed pattern switchgear offerings. The successful result of extensive in-house research and development, the GELPAG MSS provides a unique viewing window for the electrical switching contacts. The GELPAG technology advancement allows positive identification by the operator of a successfully switched procedure, such as, a HV isolation (3 x opened contacts) followed by the making of the cable side earth switch (3 x made contacts). 

Until now, the visual representation for the status for a three (3) positioned switch (CLOSED – ISOLATED – EARTHED) for an operator was limited to a “front of panel MIMIC” and accepted by industry as common practice. This was due to there being no other technology available prior the POWINS MSS which enables viewing of internal switch contacts. MIMIC indication does not provide a failsafe method of the visual indication of contacts, due to its absolute reliance on intricate linkages that move MIMIC indication flags or rotate MIMIC knobs dressed with stickers or lines, to aid in representation.

Fixed Pattern Primary Solid Dielectric Vacuum Switchgear

Addressing safe operation requirements MIMIC utilisation in fixed pattern switchgear is a step back from what industry would like to see, which are visual confirmation of the actual switch and device contacts, as is the case with the POWINS MSS Switchgear and the more expensive primary withdrawable switchgear. The POWINS MSS Switchgear breaks the traditional mould via its incorporation of viewing windows into the encapsulated pole, allowing the operator to view INSIDE the solid dielectric epoxy moulded block to view the contacts and determine the true and absolute status of the Medium Voltage Switch. The real-world outcome of this advancement is that switchgear operators can be operationally sure of the conductive contact status. This fixed pattern switchgear provides the positive isolation outcome which till now was only available with the dimensionally larger and more costly, withdrawable switchgear platforms.


Type tested and Certified in Germany, late in 2019, the POWINS MSS represents the technological advancements of world leading designers and R&D entity, GELPAG Advanced Technology GmbH.