question about a NO contact

lkandy · Sep 22, 2005

does anyone know what is a normally open contact with a arrow pointing up means.is it oneshot or holding contact.........

jolio ST · Sep 22, 2005

Is it:
A normally open contact, when closed gives a high signal (meaning from false to true; 0 to 1).

rsdoran · Sep 22, 2005

if your talking about this ^ in a contact | | or coil ( ) its called positive edge or.... depending on brand...yes its a one shot.

jstolaruk · Sep 22, 2005

The instruction is true only when the false to true transition occurs.

Kidblue · Sep 23, 2005

If it were relating to an electrical schematic, it COULD be referring to a timed contact (delay on energise etc).....just a thought!

jolio ST · Sep 23, 2005

So it really depends on the legend, right? If there is a given legend..

JohnW · Sep 23, 2005

If it is related to a microswitch or pushbutton then the arrow indicates "positive opening" this means that if the contacts weld then the mechanical operation of the switch will still force the contacts apart. This is the sort of contact used in safety circuits such as on guard limit switches and on e-stop pushbuttons

silva.foxx · Sep 23, 2005

Ikandy (is that supposed to read as 'eye candy'?)

Can you sketch the symbol in bitmap form in, say Paint, then post it for us to see. "A picture speaks a thousand words" and saves us guessing. Help us to help you, Doug.

stasis · Sep 23, 2005

If it's on an electrical schematic that shows control wiring, then it's a timed contact, refer to the name/number associated with the contact to find the timer. The arrow, either up or down designates wether it closes before or after the timer has timed out.

If it's a program schematic, then it's probably a one-shot.

Rod · Sep 23, 2005

I need to see the switch.

There is also a NO switch with a 'bent' arrow for toggle or joy-stick I think.

Rod (confused again)

Lancie1 · Sep 24, 2005

Guys,
Now look at what has been said: "This symbol means this...or that..depending on the brand...if in a schematic...how it is used.."

The bottom line on symbols: There is no such thing as a "standard" meaning. They mean what the user says they mean, and if you don't know what s/he meant, you better ask them.

question about a NO contact

lkandy

Member

jolio ST

Member

rsdoran

Lifetime Supporting Member

jstolaruk

Lifetime Supporting Member

Kidblue

Lifetime Supporting Member

jolio ST

Member

JohnW

Member

silva.foxx

Member

stasis

Member

Rod

Member

Lancie1

Lifetime Supporting Member

Similar Topics