genç arkadaş ' Alıntı:
Şalt sahası topraklaması koruma topraklamasıdır. Koruma ve işletme topraklamaları birleştirilmemelidir.
(iç topraklamaya mı yoksa dış topraklamaya mı bağlanmalı?) Dış topraklamadan kastınız galiba gövde topraklaması. İç toraklamadan kastınız da işletme topraklaması.
Generatör nötürü ile trafo nötürü zaten birleşiktir. Bunun topraklaması ise işletme topraklaması diye nitelendirilir.
Generatörlü işletmelerde üç topraklama yapılır:
1-Generatör ve trafo topraklaması (işletme),
2-Trafo gövdesi (koruma),
3-Generatör gövdesi.
Trafo ve generatör gövde topraklamalarının ayrı yapılma sebebi ise şudur:
Trafo gövdesine yüksek gerilim temasında generatörün zarar görmemesi.
Hocam, okuduğum dökümandan alıntı şöyle:
"...
Grounding and Lightning Protection Eguipment
Grounding and Lightning Protection Equipment is consistent with XTA 2206 (draft).
The following measures are taken to protect persons and equipment of the power plant against unacceptable hazards such as overvoltages.
Outdoor grounding System
This system is an intermeshed ground grid having a mesh size dependent upon the protection requirements of the buildings, the specified criteria for safety and operational grounding and the possible lightning and fault currents.
Indoor Grounding System
The items of equipment and devices inside buildings which need to be grounded are connected to a ground grid which consists essentually of ground busbars and ground ring busbars. The indoor grounding system is connected on the shortest possible routes to the outdoor grounding system and, where possible, to the reinforcement bars.
Structural Lightning Protection
In addition to standard lightning protection for buildings, further measures are taken for lightning protection of buildings containing I & C equipment. For this purpose steel rods in the structures concerned are joined by welding to form a Faraday cage and connected to the grounding system, or metal curtain materials are used as part ofthe lightning protection system.
Lightning Protection for I & C Equipment
The reference conductors of the power supply system for functionally related I & C systems are integrated into the equipment equipotential bonding grid.The I & C cables are equipped with screens which are as a rule grounded at both ends.
I & C cables important to safety run in the cable ducts from the emergency feed to the ...... building, from the switchgear to the emergency power generating and central water chiller building and on the cable bridges between the switchgear and the ....... building, are laid in cable troughs or on cable racks which are spliced over their entire length between the buldings and connected to the ground busbars in the buildings. Buried cables are provided with additional conductive screens."
