FUSIBLE FILM RESISTORS, GENERAL PURPOSE 1/8 WATT to 3 WATT Industry’s widest selection of fusible film resistors 1/8W to 3W, .1Ω to 24KΩ, 1% to 5%, leaded & surface mount Low cost, quick delivery (available on SWIFTTM program) Flameproof (UL94V0), surface-mount versions available BW Series - Axial Lead Low Cost Circuit Protection! RCD pioneered fusible film resistors in the early 1970’s as a low cost approach to circuit protection in case of overload or component failure. The component is designed to act as a conventional resistor under normal operating conditions, but open quickly under fault conditions. Series BW meets the requirements of EIA RS-325 and can be useful in eliminating circuit board damage and fire hazards. Standard fusing characteristics can be altered to customer requirements. OPTIONS Modified fusing characteristics (fast blow, slow blow, etc.) Increased pulse capability (Option P) Dozens of additional options are available... Mil-spec screening/burn-in, special marking, non-standard values, custom lead forming, increased power or voltage, etc. Customized components are an RCD specialty! ← →← L → H ↓D BW Inch [mm] ↓d ↑ ↑ Dimensions BW Series (Axial Lead) Wattage Resistance Rating 1 Range 1 RCD Type Voltage Rating 1, 2 MBW Series - SM MELF L ± .032 [.8] D ± .024 [.6] d ±.003 [.07] H (Min.) 1/8W 1Ω to 10K 200V .145 [3.7] .067 [1.7] .020 [.5] 1.00 [25] 1/4W 0.1Ω to 10K 200V .250 [6.4] .090 [2.3] .022 [.55] 1.02 [26] .256 [6.5] BW1/2F, MBW1/2F 1/2W 0.1Ω to 24K 250V .354 [9.0] .128 [3.3] .025 [.6] 1.02 [26] .374 [9.5] BW1/2FS, MBW1/2FS 1/2W 0.2Ω to 20K 250V .250 [6.4] .090 [2.3] .022 [.55] 1.02 [26] .256 [6.5] BW1F, MBW1FS 1.0W 0.1Ω to 24K 300V .375 [9.5] .135 [3.4] .026 [.65] 1.02 [26] .374 [9.5] BW2F, MBW2F 2.0W 0.1Ω to 24K 300V .450 [11.4] .162 [4.1] BW3F, MBW3F 3.0W 0.1Ω to 24K 350V Expanded range available 2 B C ↑ A ± .012[.3] BW1/8F 1 ↓ MBW Dimensions MBW (MELF) BW1/4F, MBW1/4F .60±.062[15.2±1.6] .22±.032[5.6±.8] ←A→ ↑ RoHS Term.W is RoHS compliant & 260°C compatible ↓ BW/MBW SERIES RESISTORSCAPACITORSCOILSDELAY LINES B (Max.) C (Min.) N/A .118 [3] .040 [1] .154 [3.9] .060 [1.5] .118 [3] .040 [1] .154 [3.9] .060 [1.5] .031[.8] 1.02 [26] .441[ 11.2] .031[.8] 1.37 [35] .598 [15.2] .220 [5.6] .197 [5] .080 [2] .080 [2] Maximum working voltage is determined by E = (PR)1/2, E should not exceed value listed. 60 50 3F 2F 1F, 1FS 20 1/4F 30 1/2F, FS 40 1/8F FUSING TIME (SECONDS, TYP.) FUSING CHARACTERISTICS 10 0 5 10 15 20 30 40 50 60 80 100 APPLIED POWER (WATTS) APPLICATION NOTES: 1. Fault level must be suitable to safely open the resistor quickly, especially surface mount MBW models. If insufficent, the resistor may reach elevated temp. For this reason, the fusing overload must be relatively large compared to rated W, 20 to 50x is common for most axial-lead applications, 40 to 100x for most SM circuits. SM fusing times vary due to mounting geometry/materials, so each application needs to be evaluated by user. The fault condition must be at least equal to the minimum W indicated in each of the above curves, and preferably double for SM applications. Fusing may still occur at W levels below the levels graphed above but not consistently (fast-blow models available). Don’t exceed volt rating or 200x W rating, whichever is less (increased levels available). 2. For customized models, complete RCD’s Fuse Questionnaire or advise the desired fusing wattage or current, min.& max. blow time, continuous wattage, ambient temp., pulse conditions, physical constraints, voltage to be interrupted, frequency, etc. 3. Maintain clearance from any heat-sensitive or flammable materials. 4. Fusing times vary depending on resistance value. Typical fusing times are given above for 1Ω - 3.9K. Low values tend to fuse slower. Consult factory for assistance. 5. Residual resis. is ≥50x initial value after fusing at 20x rated W (30x for BW1/8F & MBW) 6. Verify selection by evaluating under the full range of fault conditions. Place resistors inside a protective case when testing. TYPICAL PERFORMANCE Temperature Coefficient 200ppm/°C Load Life Stability 5% Operating Temp. Range -55 to +165°C Power Derating 0.71%/°C >25°C Dielectric Strength 500V (300V BW1/8F) P/N DESIGNATION: BW1F - 101 J T W RCD Type Options (leave blank if standard) Resis.Code 1%: 3 signif. figures & multiplier, (R100=.1Ω,1R00=1Ω,10R0=10Ω,1000=100Ω, etc.) Resis.Code 2%-10%: 2 signif. figures & multiplier, (R10=0.1Ω, 1R0=1Ω, 100=10Ω, 101=100Ω, etc.) Tolerance: J=5% (std.) G=2%, F=1% Packaging: B=Bulk, T=Tape & Reel Termination: W = Lead-free, Q = Tin/Lead (leave blank if either acceptable) RCD Components Inc, 520 E.Industrial Park Dr, Manchester, NH, USA 03109 rcdcomponents.com Tel: 603-669-0054 Fax: 603-669-5455 Email:[email protected] FA037D Sale of this product is in accordance with GF-061. Specifications subject to change without notice. 81