Current Sensing Four Terminal Resistors

(LSQ)

Product Introduction (LSQ)

Four Terminal Resistor for Kelvin Connection LSQ Series
4-Wire Power Precision Current Sense (LSQ) Series
Thumbnail Gallery

Token's Kelvin style (LSQ) family current sensing 4-terminal resistors handle high-wattage applications. Providing ultralow resistance values (to 0.01 ohm) for relatively high current requirements, new four-terminal cement filling resistor from Token combine the advantages of a Kelvin configuration with PC board mounting capability.

The Kelvin (or 4-terminal) configuration enables current to be applied through two opposite terminals and a sensing voltage to be measured across the other two terminals, eliminating the resistance and temperature coefficient of the terminals for a more accurate current measurement.

The 4 lead resistors are a new version of Token's (LSQ) Precision Current Sensing Family Resistors which was specially designed for use in a Kelvin method where a current is applied through two opposing leads and sensing voltage is measured across the other two leads. Token LSQ series is specifically designed for low resistance applications requiring the highest accuracy and temperature stability.

The advantages of Kelvin connection enable the resistance and temperature coefficient of the leads to be effectively eliminated. The need to connect to the leads at precise test points is eliminated, allowing for tighter tolerance on the end application. Also results in a lower temperature coefficient of resistance and lower self-heating drift which may be experienced on two-terminal resistor.

Token will also produce low ohmic resistor LSQ series outside these specifications to meet customer requirements.
Contact us with your specific needs.

Features :

  1. Welded & fireproof construction.
  2. Superior anti-surge capability & Low TCR.
  3. Special inorganic potting construction provides
    high moisture resistance and thermal conductivity.
  4. 4 leads for Kelvin connection with extremely low resistance values.

Applications :

  1. Automatic Test Equipment.
  2. Current Sensing Application.
  3. High Precision Instrumentation.
  4. Industrial, Medical and Military.
  5. Measurement Instrumentation.

Specification & Dimensions (Unit: mm) (LSQ-A) for Kelvin Connection

4-T Kelvin Sensing (LSQ-A) Dimensions4-T Kelvin Sensing (LSQ-A) Dimensions
Type Power
(Watts)		 Resistance Range
(Ω)		 Dimensions (Unit: mm)
L W±1 H±1 P±1 d±0.5
LSQ-A-3 3 R01~R1 22±1.0 8 8 14 0.8
LSQ-A-5 5 R01~R1 22±1.5 9.5 9.5 14 0.8
LSQ-A-7 7 R01~R1 35±2.0 9.5 9.5 25 0.8
LSQ-A-10 10 R01~R1 48±2.0 9.5 9.5 36 0.8
LSQ-A-15 15 R01~R1 48±2.0 12.5 12.5 36 0.8

Specification & Dimensions (Unit: mm) (LSQ-B) for Kelvin Connection

4 Terminal Sensing (LSQ-B) Dimensions4 Terminal Sensing (LSQ-B) Dimensions
Type Power
(Watts)		 Resistance Range
(Ω)		 Dimensions (Unit: mm)
L±2 W±1 H±1 P±1 P1±1 d±0.5
LSQ-B-5 5 R01~R1 26 5 10 20 12 0.8

Specification & Dimensions (Unit: mm) (LSQ-C) for Kelvin Connection

4-wire Sensing (LSQ-C) Dimensions4-wire Sensing (LSQ-C) Dimensions
Type Power
(Watts)		 Resistance Range
(Ω)		 Dimensions (Unit: mm)
L±2 W±1 H±1 P±1 P1±1 d±0.5
LSQ-C-10 10 R01~R1 18 10.5 20 12 5 1.0

Power Derating Curve (LSQ)

(LSQ) Power Derating CurvePower Derating Curve (LSQ)

Characteristic Specification (LSQ)

Kelvin 4 Lead configuration (LSQ)Kelvin 4 Lead configuration (LSQ)
Test Items Test Method Specification
Resistance Tolerances   D(±0.5%), F(±1%), G(±2%), J(±5%)
Temperature Coefficients   ±100 ppm/°C
Operating Temperature Range   -55°C~275°C
Maximum Working Voltage   (P40°C x R)1/2
Terminal Tensile Strength 50N, 10s ΔR≤±1.0%R
Withstand Voltage 1000V, 1 Min. No damage on the appearance.
Short Time Overload 5 times rated power, 5s ΔR≤±4.0%R
Thermal Shock -55°C~+275°C, 5 cycles, 30 min. ΔR≤±5.0%R
Load Life 40°C, 1000h 1.5 hours on, 0.5 hours off. ΔR≤±5.0%R

Order Codes (LSQ)

LSQ-A - 15 R01 J P
1 2345
Part Number
LSQ-A
LSQ-B
LSQ-C
  
Rated Power
3 3 Watt
5 5 Watt
7 7 Watt
10 10 Watt
15 15 Watt
Resistance Value (Ω)
R01 0.01Ω
R05 0.05Ω
R1 0.1Ω
Tolerance
J ±5%
Package-Code
P Bulk

Specification Download (LSQ)

Download Complete (LSQ) Series Specification PDF Sheet (414KB) Power Precision Current Sensing 4-Terminal Resistor.

Four-terminal probes method is an electrical impedance measuring technique that uses separate pairs of voltage-sensing and current-carrying electrodes to make more accurate measurements than traditional two-terminal (2T) current sensing.
4-terminal sensing (4T sensing) resistor is also known as Kelvin sensing, 4-lead probes, or 4-wire sensing resistor.