4R1

4R1 is a marking commonly found on electronic resistors to indicate a resistance value of 4.1 ohms. The "R" serves as a decimal point, allowing compact printed codes on both axial and surface-mount resistors. Consequently, values such as 1R0, 4R1, and 10R0 correspond to 1.0 Ω, 4.1 Ω, and 10.0 Ω, respectively. This form of notation is widely used because it avoids the ambiguity of a decimal point in crowded markings.

In resistor markings, the 4R1 code conveys the base resistance, while tolerance and other characteristics are typically indicated by additional markings, bands, or packaging rather than by the three-character code alone. Common tolerances for resistors include ±1%, ±5%, and ±10%, with precision parts sometimes showing a temperature coefficient separately.

The 4R1 marking appears on different resistor formats, including through-hole axial types and surface-mount device (SMD) types. While the format is widely recognized, exact marking conventions can vary by manufacturer, so cross-checking with the component’s datasheet is advisable for critical applications.

Other uses of the string "4R1" may exist in different product lines or catalogs as an internal model, lot, or code. However, outside resistor marking, there is no single universal meaning for 4R1, and its interpretation is context-dependent.

In summary, 4R1 primarily denotes a 4.1-ohm resistance in electronic components, using the R as a decimal point to fit onto compact resistor markings.