KEY NC
Key-operated normally-closed switch
A key-operated NC switch opens its reference closed contact through the key mechanism.
Schematic
IEEE / ANSI · KEY NC
ANSI/IEEE Key-operated normally-closed switch form
IEEE-library form of key-operated normally-closed switch: a key-operated NC switch opens its reference closed contact through the key mechanism.
In plain English
What does ANSI/IEEE Key-operated normally-closed switch form mean?
This reference locates key-operated normally-closed switch in Autodesk's IEEE-oriented miscellaneous switches family. A key-operated normally closed switch opens its reference closed contact through the key mechanism. Its access and switching functions must be documented separately. The public library uses HPB12KS for its horizontal representation; this is a vendor block name, not an IEEE standards symbol number.
A simple example
Read the operating mechanism and the contact reference state together. Cross-reference every associated contact to the same device and show which movement, signal or reset changes its condition; the symbol alone does not establish the complete switching sequence.
What the drawings help you do
Read the reference position from the operator schedule. normally closed identifies the contact reference state, not a guarantee of tamper-proof control. The linked functional counterpart explains the same operating role in its own drawing context; agreement of every detailed convention mark is not asserted.
This particular reference
IEEE-library form of key-operated normally-closed switch: a key-operated normally closed switch opens its reference closed contact through the key mechanism. normally closed identifies the contact reference state, not a guarantee of tamper-proof control.
- Normally open / normally closed
- The contact state in the normal condition defined for the drawing.
- Signal
- Electrical information passed between devices, rather than necessarily the main power supply.
- Rating
- A value stating the conditions for which equipment is specified.
Read the source: Autodesk IEEE Symbol Preview — Miscellaneous Switches
IEEE / ANSI · Key Switch, Normally Closed
Autodesk IEEE Symbol Preview: Miscellaneous Switches, block HPB12KS. Matching functional counterpart linked separately. Independently drawn educational geometry; not a certified IEEE glyph or database identifier.
Shown as an independently authored educational illustration. Use the cited publication and drawing legend to verify the required drafting form.
Schematic · KEY NC
What it represents
This reference locates key-operated normally-closed switch in Autodesk's IEEE-oriented miscellaneous switches family. A key-operated NC switch opens its reference closed contact through the key mechanism. Its access and switching functions must be documented separately. The public library uses HPB12KS for its horizontal representation; this is a vendor block name, not an IEEE standards symbol number.
Read the operating mechanism and the contact reference state together. Cross-reference every associated contact to the same device and show which movement, signal or reset changes its condition; the symbol alone does not establish the complete switching sequence.
Read the reference position from the operator schedule. NC identifies the contact reference state, not a guarantee of tamper-proof control. The linked functional counterpart explains the same operating role in its own drawing context; agreement of every detailed convention mark is not asserted.
How to read it
- Read the reference position from the operator schedule.
- The preview is an original explanation of this function. Match the actual drawing convention to its legend and the selected equipment documentation.
Information to show or reference
- Define normal key position
- State contact action
- Reference key-removal restrictions
A distinction that matters
NC identifies the contact reference state, not a guarantee of tamper-proof control.
Sources you can follow
These public references support the explanation and provide further detail. Their graphics and downloadable files remain with their publishers.
Autodesk IEEE Symbol Preview — Miscellaneous Switches
Public IEEE-oriented Miscellaneous Switches table explicitly lists HPB12KS as Key Switch, Normally Closed. This supports the vendor convention context, not reproduction of the publisher graphic.
About this graphic
This illustration was authored independently by Elora Grid to explain the concept. It is not reproduced from a customer drawing, an official standard graphic or a manufacturer CAD file. Its correspondence to an exact IEC or IEEE symbol identifier has not been certified.
SVG and DXF downloads contain this original artwork. DXF uses unscaled drawing units; a GA envelope supplies no product dimensions, clearances or fabrication information. Original artwork is available under CC BY 4.0. Third-party references retain their own terms.
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