F
Symmetric gas discharge tube
A protective gas discharge tube drawn with identical electrodes either side, listed as a distinct symmetric form.
IEC
IEEE / ANSI · F
ANSI/IEEE Symmetric gas discharge tube form
IEEE-library form of symmetric gas discharge tube: a protective gas discharge tube drawn with identical electrodes either side, listed as a distinct symmetric form.
In plain English
What does ANSI/IEEE Symmetric gas discharge tube form mean?
This reference locates symmetric gas discharge tube in Autodesk's IEEE-oriented miscellaneous family. The publisher's IEC-oriented library lists a symmetric protective gas discharge tube separately from the standard form. The symmetric drawing presents both electrodes identically, emphasising that the device behaves the same for either polarity of surge, as is typical for AC and signal line protection. The public library uses HFU1_S00375 for its horizontal representation; this is a vendor block name, not an IEEE standards symbol number.
A simple example
Use the surrounding circuit labels and the project legend to identify the intended operating condition and connection. Carry the same device reference into the schedule or equipment document so the symbol can be reconciled with its real terminals, function and operating limits.
What the drawings help you do
The symbol is a drawing variant and does not establish electrical ratings. Breakdown voltage, impulse current and follow current behaviour come from the product data. Readers should not infer three-terminal construction from this form; three-electrode tubes need their own representation. Read ratings from the product data, not the symbol. The symmetric form draws identical electrodes; the standard gas discharge tube form may show the electrodes differently. 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 symmetric gas discharge tube: a protective gas discharge tube drawn with identical electrodes either side, listed as a distinct symmetric form. The symmetric form draws identical electrodes; the standard gas discharge tube form may show the electrodes differently.
- AC
- Alternating current: electricity whose direction changes periodically.
- Terminal
- An identified point where a conductor connects.
- Signal
- Electrical information passed between devices, rather than necessarily the main power supply.
Read the source: Autodesk IEEE Symbol Preview — Miscellaneous
IEEE / ANSI · Protective Gas Discharge Tube, Symmetric
Autodesk IEEE Symbol Preview: Miscellaneous, block HFU1_S00375. 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 · F
What it represents
This reference locates symmetric gas discharge tube in Autodesk's IEEE-oriented miscellaneous family. The publisher's IEC-oriented library lists a symmetric protective gas discharge tube separately from the standard form. The symmetric drawing presents both electrodes identically, emphasising that the device behaves the same for either polarity of surge, as is typical for AC and signal line protection. The public library uses HFU1_S00375 for its horizontal representation; this is a vendor block name, not an IEEE standards symbol number.
Use the surrounding circuit labels and the project legend to identify the intended operating condition and connection. Carry the same device reference into the schedule or equipment document so the symbol can be reconciled with its real terminals, function and operating limits.
The symbol is a drawing variant and does not establish electrical ratings. Breakdown voltage, impulse current and follow current behaviour come from the product data. Readers should not infer three-terminal construction from this form; three-electrode tubes need their own representation. Read ratings from the product data, not the symbol. The symmetric form draws identical electrodes; the standard gas discharge tube form may show the electrodes differently. 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 ratings from the product data, not the symbol.
- Check whether a three-electrode tube is intended instead.
Information to show or reference
- State sparkover voltage and impulse rating.
- Show the earth or return side.
- Keep the form consistent with the legend.
A distinction that matters
The symmetric form draws identical electrodes; the standard gas discharge tube form may show the electrodes differently.
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
Public IEEE-oriented Miscellaneous table explicitly lists HFU1_S00375 as Protective Gas Discharge Tube, Symmetric. 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.
Explore related references
GDT
Gas-discharge protection tube
A gas-discharge tube provides a documented surge-protection path through gas breakdown.
SLD / Schematic
GDT
ANSI/IEEE gas discharge tube symbol
IEEE-oriented protective gas discharge tube: electrodes within a sealed envelope that conduct when voltage exceeds breakdown.
IEEE / ANSI
F
Double spark gap
A spark gap form with two gaps sharing a common electrode, used to protect two conductors against a common earth.
IEC
Put the reference into a drawing workflow.
Elora Grid helps electrical teams work with drawings, specifications and equipment information. Explore the drafting workflow or join the early-access waitlist.