Precision Wirewound Resistors (BWW)

(BWW) Precision Power Resistors Operate in Harsh Environments.

The new BWW series moulded axial leaded wirewound resistors from Direct use high-purity alumina ceramic cores with wire winding which are spot welded by precision CNC machine tools to ensure total operational consistency throughout.

Also, using advanced encapsulation die/mould technologies, this precision power resistors are encapsulated with epoxy molding compound.

The BWW models possess a wide resistance value from 0.1Ω to 39KΩ and meets the stringent requirements of MIL-R-93. Ayrton Perry noninductive windings are available on request. The BWW precision version has low ohmic values for current sensing applications.

All versions are miniaturised for better power to dimension ratios and are available in 0.5W to 10W rated power at 25°C. Tolerance is available in ±0.1%, ±0.25%, ±0.5%, ±1% and ±2% with TCR ±25PPM/°C, ±50PPM/°C and ±150PPM/°C which makes them ideally suited for use in precision applications.

The BWW series is RoHS compliant with 100% Sn (lead free) coated terminals. To address your need for technical and economic success in a timely manner, our custom solutions are the best option. Contact us with your specific needs.

Download complete PDF Precision Wirewound Resistors (BWW).

Features :
  1. Axial Moulded
  2. Excellent load life stability
  3. Insulation, Moisture Proof
  4. High Precision and reliability
  5. Meets the Standards of MIL-R-93
  6. RoHS compliant with 100% lead free
Applications :
  1. Electrical loads, Filament dropping
  2. DC/DC converters, AC/DC inverters
  3. High-voltage bleeders, Dynamic braking
  4. Capacitor charging/discharging regulation
  5. Motor speed controls, Voltage divider networks
  6. Bias supply, Current shunts, Voltage dropping, Crow-bar circuits
Technical Specifications (BWW)
Type Rated Watts
at 25°C
Resistance Range
Dimensions (Unit: mm)
Min Max A±0.25 ΦB±0.25 Φd F
BWW-0.5 0.5 0.1 100 ±0.1
7.0 3.0 0.6 27.0
BWW-1 1.0 0.1 1K 11.0 3.0 0.6 31.0
BWW-3 3.0 0.1 10K 15.0 5.2 0.8 34.0
BWW-4 4.0 0.1 15K 18.0 6.5 0.8 38.0
BWW-5 5.0 1 24K 24.0 8.4 1.0 44.0
BWW-10 10.0 1 39K 46.5 10.0 1.0 66.0
Electrical Performance (BWW)
Test Items Test Conditions Specifications
Operating Temp. Range   -55°C ~ 175°C
Insulation Resistance 500V >1GΩ
Dielectric Withstanding Voltage 500V AC 1 Min. ΔR ≤ ±0.1%R
Load Life 70°C on~off cycle 1000 Hrs. ΔR ≤ ±1%R
Moisture-Proof Load Life 40°C 95% RH on~off cycle 21 Hrs. ΔR ≤ ±0.2%R
Resistance to soldering heat 350°C, 3.5s ΔR ≤ ±0.1%R
Solderability 235±5°C, 5s(solder bath method) IEC68-2-20(1968)
Order Codes (BWW)
BWW - 1W 100R F D P
Power Rating
Resistance Value
0R1 0.1Ω
100R 100Ω
1K 1000Ω
Resistance Tolerance
B ±0.1%
C ±0.25%
D ±0.5%
F ±1%
G ±2%
C ±25PPM/°C
D ±50PPM/°C
K ±150PPM/°C
P Bulk