Connecting leads to substation transformer
Connecting leads to substation transformer
(OP)
When installing an oil filled 10 MVA transformer - 69 kV to 12.47 kV with lightning (surge) arrestors mounted near to the bushings, should the incoming (outgoing) leads be:
a) connected directly to the bushings with a tap going to the arrestor;
b) connected to the arrestor and continue through (no splice)to the bushing;
c) either a or b - does not matter.
I understand that electrically they should operate the same, but is there a mechanical reason to connect the leads (500 kcmil bare copper) directly to the bushing? To me, the bushing just looks a lot more mechanically substantial than the arrestor does. I am worried abot a short circuit or icing or ?? See attached photo - hopefully I was successful in attaching it. The 69 kV arrangement is the same.
Regards,
Dave
a) connected directly to the bushings with a tap going to the arrestor;
b) connected to the arrestor and continue through (no splice)to the bushing;
c) either a or b - does not matter.
I understand that electrically they should operate the same, but is there a mechanical reason to connect the leads (500 kcmil bare copper) directly to the bushing? To me, the bushing just looks a lot more mechanically substantial than the arrestor does. I am worried abot a short circuit or icing or ?? See attached photo - hopefully I was successful in attaching it. The 69 kV arrangement is the same.
Regards,
Dave






RE: Connecting leads to substation transformer
RE: Connecting leads to substation transformer
Point to consider is your method "a" which would make the live parts as far away from the grounded parts, which can also come into play someday for limits of approach issues with vehicles ...
On a side note, the LA require their own ground conductor to carry the current when operating and not the tank, this can be one continuous for the three.
RE: Connecting leads to substation transformer
RE: Connecting leads to substation transformer
RE: Connecting leads to substation transformer
Regards
Marmite
RE: Connecting leads to substation transformer
Thanks to all for your input. I hope that I get the chance to return the favor someday.
Regards,
Dave