switched neutral

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24v hot is switched thru plc. the plc feed is common to all 16 outputs In order to stop specific output from operating under certain circumstance,I could break the neutral to that one output.
 
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Pierre C Belarge said:
Load side (secondary) conductors from a 24v source...which conductor is the "neutral" conductor?
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That's what I was trying to figure out. Thought I was missing something.
 
Then if you did that, wouldn't the output still be energized up to the point where you made the neutral break?
 
Since to switch the (so-called) neutral you would need another pair of isolated contacts, why not just put that pair of contacts immediately 'after' the PLC contacts? No confusion.

As for neutral - for one wire to be a neutral it would have to be grounded, giving the other wire a 'hot' relationship to ground. If there is no ground connection then both wires are isolated from ground, and are equal in all respects. However, one wire is, in most circuit configurations, a 'common', the return from your lamps, relays and solenoids etc. Most folks get confused when the common line is switched, cos its, well, uncommon..... (sorry, couldn't resist)
 
drees said:
In a low voltage control (24vac) is it ever acceptable by code to interlock the neutral?
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I've seen motor starters wired like this. The overload contact it in series with the coil on the neutral side.


drees said:
24v hot is switched thru plc. the plc feed is common to all 16 outputs In order to stop specific output from operating under certain circumstance,I could break the neutral to that one output.
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If you have a "hot" going to the PLC output card, than there is no neutral to break. The switching is done through the PLC's internal electronics and the "neutral" for the output switching is supplied from the backplane. Unless theres a PLC manufacturere that requires a neutral that I am unaware of, in which case it would be just as easy to switch the hot as the neutral.
 
Pierre C Belarge said:
Load side (secondary) conductors from a 24v source...which conductor is the "neutral" conductor?
Click to expand...

dbuckley said:
As for neutral - for one wire to be a neutral it would have to be grounded, giving the other wire a 'hot' relationship to ground. If there is no ground connection then both wires are isolated from ground, and are equal in all respects. However, one wire is, in most circuit configurations, a 'common', the return from your lamps, relays and solenoids etc. Most folks get confused when the common line is switched, cos its, well, uncommon..... (sorry, couldn't resist)
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Overkill said:
I've seen motor starters wired like this. The overload contact it in series with the coil on the neutral side.
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The overload contact is in series with the coil on the common side. . Don?t use the word ?neutral? or you?ll confuse somebody.

David
 
dnem said:
The overload contact is in series with the coil on the common side. . Don?t use the word ?neutral? or you?ll confuse somebody.

David
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Its statements like that that confuses people.

He said the 24VAC "hot" was feeding the PLC's outputs, in which case, the "hot" is the common.
 
The overload contact is in series with the coil on the common side. . Don’t use the word “neutral” or you’ll confuse somebody.
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Common isn't the correct word either. If it is a grounded system, then the correct term is grounded conductor. If it is an ungrounded system, there is no word for that conductor.
don
 
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