Power Low Resistance Resistors (BWL)

Direct's (BWL) power low resistance resistor minimise power consumption.

In response to demand for more energy efficient products, Direct Electronics has expanded its current sensing series offering with the launch of the BWL series, its lowest resistance value resistor, to minimise power consumption.

The BWL series has been designed for current sensing in power electronic systems and the resistors are available in 0.5W to 10W power ratings, with a wide ohmic range starting from as low as 0.005Ω.

Products in the economical, low-inductance BWL resistors are axial leads with high temperature mold compound, making them well-suited to the industry trend and are ideal for all types of current sensing applications including switching and linear power supplies, instruments and power amplifiers

In addition, the BWL series utilizes metal strip technology, essential for those involved in constructing devices and circuits for the detection of currents.

Direct's BWL standard series is lead-free and RoHS compliant and can be a replacement for Vishay, IRC, KOA, Panasonic current sense resistor with more competitive price and short lead time. Contact us with your specific needs.

Download PDF Specification Power Low Resistance Resistor.

Material :
  1. Encapsulation: High temperature mold compound.
  2. BWL metal strip technology utilizes manganin.
  3. Element: Self-supporting nickel-chrome alloy.
  4. Terminals: Tinned copper.
Features :
  1. Low inductance.
  2. Excellent load life stability.
  3. Low temperature coefficient.
  4. Cooler operation for high power to size ratio.
  5. Proprietary processing technique produces extremely low resistance values.
Applications :
  1. Switching and linear power supplies.
  2. Notebook power management.
  3. Power amplifiers.
  4. Instruments.
Technical Specifications & Dimensions (BWL)
(BWL) Power Derating Curve
(BWL) Power Derating Curve
Low Resistance Resistor (BWL) Dimensions
Low Resistance Resistor (BWL) Dimensions
Type Power Rating
at 25°C (W)
Resistance (Ω) Resistance
Dimensions (Unit: mm)
Min Max A±0.25 ΦB±0.25 Φd F
BWL-0.5 0.5 0.01 1 ±1%
7.0 3.0 0.6 27.0
BWL-1 1.0 0.005 2 11.0 3.0 0.6 31.0
BWL-3 3.0 0.005 2 15.0 5.2 0.8 35.0
BWL-4 4.0 0.005 5 18.0 6.5 0.8 38.0
BWL-5 5.0 0.005 1 24.0 8.4 1.0 44.0
BWL-10 10.0 0.01 1 46.5 10.0 1.0 66.0
Electrical Performance (BWL)
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 (BWL)
BWL - 1W R01 F P
Part Type
Power Rating (W)
0.5W 0.5 Watt
1W 1.0 Watt
3W 3.0 Watt
4W 4.0 Watt
5W 5.0 Watt
10W 10.0 Watt
Resistance (Ω)
R01 0.01Ω
0R1 0.1Ω
Tolerance (%)
F ±1%
G ±2%
J ±5%
P Bulk