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The 10 GE AC Disconnects that comprise their list of Spec-SetterTM Safety Switches are categorized fused, no fuse and non-automatic. I want to know the definition of a non-automatic AC disconnect.

GEs Non-automatic disconnects are drawn as:

Schematic symbol of the GE Non-automatic AC Disconnect

Which appears to be a ganged two pole switch. Would a Non-automatic AC Disconnect then be an enclosure with a movable handle on its side, or a rotary switch maybe, so it can be switched off and on manually from outside the enclosure, so you don't have to open the box and pull out the disconnect switch?

Or is there more going on that I am missing, like some application for which it is often used other than disconnecting an AC, or some advantage it gives a user?

I searched for information about "Non-automatic" AC disconnects, but could not find a definition or anything else about them.

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    I would guess it means "manual switch".
    – Hot Licks
    May 15 at 21:34
  • @HotLicks As you can see, I already guessed the same. Can you point me to a reference that defines that, or explains it, so I know it to be true? I am hoping that someone who is very familiar with the term will answer my question.
    – Guiermo
    May 15 at 23:06

2 Answers 2

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A "non-automatic" disconnect is a molded case switch in a box

All fusible and most non-fusible AC disconnects are of a type known as a "pullout disconnect" where there are fuses or blades in a carrier that fits into a set of jaws on both ends. This is a very inexpensive way to produce a reasonably functional disconnect, but has the disadvantage of not being well-suited for frequent operation.

The "non-automatic" disconnect you're referring to, though, is different. Instead of being a pullout disconnect, it uses a device called a molded case switch that is essentially a circuit breaker with its trip mechanism missing. This is much more suited for frequent switching, and provides a much more user-friendly "on/off" handle, but is also more expensive than a pullout, especially considering it comes in what's essentially a tiny subpanel enclosure with its own little bus-bars vs. the integrated construction of an AC pullout disconnect.

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  • do you think your answer might be improved by replacing "The device you're referring to" by "A non-automatic disconnect"? Is a non-automatic disconnect one that can be operated without opening the box? Isn't that another advantage? I could believe that the molded case switch might be more reliable than the pullout, but wonder if that necessarily makes the pullout less suited for frequent operation, considering how often one of these needs to operate over its lifetime. Either fuses or blades maybe? There are extraneous adjectives (very, reasonably, much, much, little). Maybe?
    – Guiermo
    May 16 at 19:38
  • @Guiermo -- pullouts by their nature have their switching jaws sort of...open to the world -- imagine fumbling the pullout part into a mud puddle :P something that can't happen to a MCS May 17 at 3:49
  • and Ed Beal. Both answers seem to me decent, but. . . Pardon my ignorance, but I am new here and feel a bit trapped. I don't know how to encourage precision in answers that I feel need some wordsmithing to be held up as precisely correct. I made what I thought were good suggestions on each of the two answers, thinking edits might be made. What do I do to get well formulated answers so I can check them off as being worthy answers? Am I supposed to take all comments and the answers already given to rewrite a super answer that competes with the two already presented? I'm lost. HELP
    – Guiermo
    May 17 at 23:13
  • There are automatic pullout disconnects the fuses take the place of the shorting bar.
    – Ed Beal
    May 18 at 19:08
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Non automatic disconnect is a switch that requires a person to disconnect (no fuses).

There are really inexpensive one that has a shorting bar that is pulled out. This is the most common type in use today. When you pull it out and turn it over it doesn't make connections and says off. Pull it out and turn it over and it connects and shows the word on. Very common and these can be fused also.

The non automatic have no fuse or circuit breaker and require manual activation.

Look up non fused ac disconnect and you will find the shorting bare style Look a little further then a simple switch

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  • Suggestions: So, it's a switch, it's non fused, it has no circuit breaker, it requires a person to operate the switch to "disconnect" what? Being manually operated is part of all AC disconnects? Is that related to the name "Non Automatic"? What does the word "automatic" have to do with this? When power is ON to the HVAC and you pull out the disconnect ( name for the thingy ) and turn it over and push it back in, the word OFF is then visible, indicating that power is off. Does the last sentence belong in the answer? Second paragraph is not about the non-automatic disconnect, though important.
    – Guiermo
    May 16 at 19:55
  • There are automatic disconnects these usually have a circuit breaker and a handle that operates the circuit breaker. The handle can be locked. The shorting bar thingy is just that a bar disconnect you can call it a switch , it shorts in one orientation and not in the other call what you want some call them SHUNT BARS , the bar once removed is the disconnect if you don’t put it back in it is disconnected some sparkies keep the bar in there tool bag while working on systems. So would I call a bar disconnect a switch no I would not unless it was an old time model that pivots on 1 side.
    – Ed Beal
    May 16 at 20:17
  • and ThreePhaseEel Both answers seem to me decent, but. . . Pardon my ignorance, but I am new here and feel a bit trapped. I don't know how to encourage precision in answers that I feel need some wordsmithing to be held up as precisely correct. I made what I thought were good suggestions on each of the two answers, thinking edits might be made. What do I do to get well formulated answers so I can check them off as being worthy answers? Am I supposed to take all comments and the answers already given to rewrite a super answer that competes with the two already presented? I'm lost. HELP
    – Guiermo
    May 17 at 23:15
  • Guiermo if you need wordsmiths pick the other answer I really don’t don’t care and and the reason I quit answering because the first answer that a wannabe electrician answered was taken down and only after a licensed electrician gave an answer the word smith versions come out so vote how you will and run another pro away just done sorry, can you even see the original wannabe electrician answer that was deleted?
    – Ed Beal
    May 18 at 0:22

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