When are surge arrestors needed on medium voltage switchgear?
When are surge arrestors needed on medium voltage switchgear?
(OP)
Attached is a simplified sketch of the installation we are planning: a medium voltage (15kV) double ended switchgear that will connect to a single transformer. The new switchgear will be arc resistant and sit inside an existing electrical building.
All of the existing outside conductors are open bus. This open bus actually feeds several transformers, each one with it's own set of surge arrestors. All of the new conductors will be shielded armored 3/C cable.
My question is around surge arrestors at the new medium voltage switchgear on the incoming feeders. Are they required? Good idea to protect the switchgear?
All of the existing outside conductors are open bus. This open bus actually feeds several transformers, each one with it's own set of surge arrestors. All of the new conductors will be shielded armored 3/C cable.
My question is around surge arrestors at the new medium voltage switchgear on the incoming feeders. Are they required? Good idea to protect the switchgear?






RE: When are surge arrestors needed on medium voltage switchgear?
If you have TP and TC it will be necessary.
If you don´t know ,its better to install;- surge arrester is not so expensive.
It is less expensive then the studies necessary to proof you need surge-arrester.
RE: When are surge arrestors needed on medium voltage switchgear?
TP?
TC?
RE: When are surge arrestors needed on medium voltage switchgear?
RE: When are surge arrestors needed on medium voltage switchgear?
You could review IEEE Std C62.22, IEEE Guide for the Application of Metal-Oxide Surge Arresters for Alternating-Current Systems, for calculation of how far you can go with the cable before you need arresters at the end while maintaining adequate protective margins.
More than likely, at 15 kV, you won't need arresters at the switchgear. But, as odlanor points out, the arresters may be less expensive that the study required to prove that they aren't needed.
RE: When are surge arrestors needed on medium voltage switchgear?
G.F.
www.engineering-services.gr
RE: When are surge arrestors needed on medium voltage switchgear?