LangJie RXF-2WS-200R-70mm-TB

This standard applies to wire-wound resistors used in home appliances, computers, information technology, and lighting applications. Wire-wound resistors are designated by RXF; rated power is expressed numerically; nominal resistance values are given in Ω, KΩ, or MΩ; total length is the sum of lead and body length, in MM. Tolerance is measured by bridge method at room temperature and must fall within the specified tolerance of the nominal resistance value; a ±5% tolerance need not be marked. Processing/packaging options include taped (boxed) and bulk; digits marked at both ends of the sleeve indicate the length not covered by the sleeve; forming methods include vertical and horizontal forming. Rated power applies to the maximum load voltage and overload voltage at an ambient temperature of 70℃; when ambient temperature exceeds 70℃, the power derating curve applies. Outline dimensions are in MM. The substrate is a ceramic rod of Japanese or German manufacture; terminals are tin-plated CP wire for electrical use; the resistor body is coated with gray flame-retardant insulating paint, rated to 800℃, with a hard surface that must not flake or peel. The resistor body is printed with 5 distinct color bands: bands 1–3 indicate resistance value, band 4 indicates tolerance, and band 5 (white) indicates the identification code. Operating temperature range: -25℃ ~ 155℃.

Regarding mechanical performance: in the tensile strength test, one end of the resistor body is fixed and force is applied to the other end along the axial direction of the resistor body, increasing the load to 1.5 kg and holding for 10 seconds — no detachment or loosening is permitted. In the torsion strength test, the terminal lead is bent 90° at a radius of approximately 0.8 mm at a point approximately 6 mm from the resistor body; the terminal lead is then clamped at a point 1.2 ± 0.4 mm from the bent point toward the lead end, using the terminal lead axis as the rotation axis, and rotated 360° in one direction and then 360° in the reverse direction in approximately 5 seconds per rotation, repeated twice in each direction — no breakage or loosening is permitted.

Regarding electrical performance: fusing characteristics can be provided upon customer request. The temperature coefficient formula is: Temperature Coefficient (ppm/℃) = ((R2 − R1) ÷ R1) × (1 ÷ (T2 − T1)) × 10^6, where R1 is the resistance before test, R2 is the resistance after test, T1 is room temperature, and T2 is the test temperature (room temperature + 50℃). Under short-time overload, application of 2.5 times the rated voltage for 5 seconds must produce no abnormality, and the resistance change rate after cooling for 30 minutes must be within ±1%. For the dielectric strength test, the resistor under test is placed in a V-shaped metal trough or wrapped in tin foil; one terminal serves as one electrode and the surface of the metal trough or tin foil as the other; 350 VAC is applied for 1 minute, followed by the maximum overload voltage for 1 minute — no abnormality or burn damage is permitted after the test, and the resistance change rate must be within 0.5%. For the insulation resistance test, the resistor under test is placed in a V-shaped metal trough or wrapped in tin foil; one terminal serves as one electrode and the surface of the metal trough or tin foil as the other; insulation resistance measured with a DC 500 V insulation tester must be 10,000 MΩ or more. For the humidity endurance test, the resistor is subjected to 500 ± 2 hours in a constant temperature and humidity chamber at 40 ± 2℃ and 90 ~ 95% RH, with a cycle of rated power applied for 1.5 hours on and 0.5 hours off; after being left unloaded indoors for approximately 1 hour, the resistance change rate must be within ±5% and the appearance must show no significant change and remain clearly legible. For the load life test, the resistor is subjected to 1,000 ± 4 hours in a 70℃ chamber with a cycle of rated voltage applied for 1.5 hours on and 0.5 hours off; after cooling for 1 hour, the resistance change rate must be within ±5%.