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What is this schematic symbol?

  1. Mar 10, 2015 #1
    See attached image.

    This is part of a one-line diagram of a solar-with-battery backup power supply system. Two inverters, one for the batteries and one for the solar panels, feed these things (one of which I've circled in red) at the inputs to a splitter, which splits the load between the two sources. I think the mystery symbol represents a current or power sensor integral to the splitter, but I'm not sure.

    The drawing was made by a Canadian and therefore contains a mix of American and European symbols, but the client was in Tanzania, so it could be African as well. We use the client's country's symbols if we know them.

  2. jcsd
  3. Mar 10, 2015 #2
    I think it is a disconnect box - like a switch. Agreed it is not ideal. People actually die from this type of misunderstanding - so please pay attention.
  4. Mar 10, 2015 #3


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    It is a Disconnect w/o fuse protection. Basically a knife blade switch with the appropriate Amp rating (not stated, but implied). These types of Disconnects come in the standard ratings: 20 A, 30 A, 60 A, 100 A, .... on up.

    A fused Disconnect would have a diagonal line thru it and often a note for the size of fuse (which could be any value up to the rating of the disconnect),

    A cross on this symbol would NOT be a disconnect but a combination motor starter.
  5. Mar 24, 2015 #4
    Thanks. I've been able to confirm that it is a disconnect switch.
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