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  1. Default pad mount transformers, underground feeders question

    We have a 5 kv distribution line dead ended on a dip pole. There are three solid blade/porcelain "chocolate box" type disconnects feeding one set of 3 phase undergrounds. There's about a quarter mile of underground feeding three 500 kva pad mounts for various commercial properties.

    A few months back, I got sent out to pull these disconnects so a contractor could work on a service. It was 5 am and pitch dark out. I pull the first one, when I pulled the second, it drew an arc fully open. I remembered some old time telling me if that happens, wave the stick through the arc to kill it. That didn't work and this thing was blazing. Now I can't see sh*t with the ball of fire to get the hot stick into the hole to try to close it. I get it closed. Second try, I get it open without an arc. The third one opens fine.

    OK, so now I know that these solid blade switches are not made to break a load and there is no means to put a load buster on them.

    I can't kill this whole circuit in the future because it feeds a couple of neighborhoods too.

    If I have to get these transformers off in the future, would you pull the elbows off of the bushings with a hot stick live? I've never done this or seen it done. What about re-energizing it? Would you only do it if you had access to the building to kill the load on the secondaries? I know if the elbows have white bands they are load break elbows, but I have no training on practical methods involving UG and pad mounts, any tips would be greatly appreciated.

    Maybe the best thing would be to change out the chocolate boxes to some decent switches, but in the meantime, I'm stuck with what is there.

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