1. Separate the taper law from total resistance

A stock line containing a potentiometer's total resistance leaves a second identification question unanswered: how does the documented output change as the moving contact travels? Vishay Sfernice's application note defines resistance taper through that position relationship. The same note defines total resistance separately. A seller preparing mechanical controls for review should preserve both descriptions instead of expecting one nominal resistance entry to communicate the response law.

The distinction concerns what a specification describes. Total resistance identifies the resistive element's overall value in the manufacturer's terminology. Taper relates contact position to the selected resistance, or to a stated output ratio. Recording only the overall value removes the positional relationship. It therefore leaves the reviewer unable to tell whether the available records establish the taper requested in the enquiry.

Begin with the actual manufacturer's complete control reference and the applicable product document. Keep any nominal value already recorded, but add only the taper wording that can be linked to that identity. A missing taper is a specific documentation gap. It should remain visible even when the resistance value, package and quantity are otherwise well described; no response curve is supplied by those other fields.

2. Keep travel and reference conventions with the law

A position relationship needs its original reference. Vishay distinguishes the full mechanical travel from the effective electrical travel over which the specified resistance law applies. These terms answer different questions about the control. A record describing a shaft's movement should not silently become a description of the entire electrical relationship, particularly when the original document's reference has been omitted from a shortened inventory note.

The note also defines the viewing basis for rotation direction and gives designated reference points for output quantities. Preserve those conventions when summarising a taper description. Clockwise wording copied without its observation basis can lose useful context, while an output ratio without its stated reference can describe an incomplete relationship. This guide uses the distinctions qualitatively and provides no terminal numbering, curve, angle or ratio calculation.

If an existing description mixes a shaft position, a resistance reading and a catalogue taper, label each by what it represents. Retain the original document reference so the recipient can resolve the interpretation. Do not supply a presumed midpoint or reconstruct a curve to fill the gap. The decision is whether the records explain the specified law, rather than whether an undocumented measurement can be inferred.

3. Retain the exact family option and special-order record

A family document may describe more than one taper context. Bourns' 3310 material includes a linear-taper heading and a statement about audio-taper versions as special orders. That historical wording is a reason to preserve the actual option record. It does not establish today's orderability, identify a seller's control or turn the family name alone into a complete taper description.

Keep an original purchase reference or special-version description with the units it identifies. Where the offered control's records do not resolve the option, retain the family-level information as context and the taper as unconfirmed. A familiar letter or a similar part from another programme should not replace the applicable manufacturer's explanation. No taper-letter decoder or comparison of audio response laws is provided here.

For a mixed group, separate the identities supported by their own option records from those described only by total resistance. This preserves the useful difference between a documented taper and an unresolved version. It also avoids a broad family quantity being presented as one response type merely because the controls look alike or were stored together after the original programme ended.

4. Separate catalogue law from the offered control condition

A documented taper concerns nominal product identity. It is not a report of the present wiper position, actual response, contact wear or history of adjustment. Keep any existing condition observation attached to the particular control or group it covers. A readable option record can resolve the intended taper while leaving the physical item's current behaviour entirely unassessed.

Submit the supported law, total resistance and reference conventions as distinct parts of the description. Use the general excess-stock list for release authority and quantities, rather than repeating a generic packing checklist under every technical field. For an ICULTRA control enquiry, explain the specific missing option or reference. This preparation does not adjust the controls, establish a measured curve or promise acceptance of the offered material.

Sources and further reading

Vishay’s application-note definitions and the bounded Bourns3310 statements support the terminology and option examples. No taper curve, terminal map, response measurement or current special-order availability is supplied.