TCS8440T Current Sensing Resistors
The TCS8440T is a four-terminal, bus-bar, metal strip current shunt assembled using electron beam welding. It is rated at up to 36W and carries a continuous current of 840A at a fixed resistance of 0.05mΩ, with a tolerance of ±5%, at terminal temperatures not exceeding 140°C.
The series achieves a temperature coefficient of resistance (TCR) of less than ±100ppm/°C and operates across a temperature range of −40°C to +170°C. Long-term stability is excellent, with resistance drift not exceeding ±1.0% after 1000 hours at +125°C. Vibration resistance is rated to ±0.5% across a 10–2000Hz sweep at 5g. The TCS8440T uses tap-type voltage sensing terminals exclusively, providing a compact and consistent Kelvin connection for integration into busbar and panel wiring environments.
What are the TCS8440T Current Sensing Resistors?
The TCS8440T is a high-current precision shunt resistor designed for accurate current measurement in power electronics and industrial systems. Its four-terminal (Kelvin) architecture keeps the voltage-sensing taps entirely separate from the main current path, eliminating contact and lead resistance from the measurement circuit and ensuring that the 0.05mΩ element resistance is what the instrumentation sees — not a composite of the element plus connection parasitics.
Assembly by electron beam welding produces a metallurgically bonded joint between the copper bus-bar current terminals and the resistive alloy strip. This method delivers the joint integrity and dimensional consistency needed for stable, repeatable resistance in high-cycle and thermally stressed environments. The flat bus-bar geometry minimises stray inductance, preserving measurement accuracy during fast transient events and at the switching frequencies encountered in modern power conversion circuits.
The tap-type voltage sensing configuration places the sensing connections directly on the resistive element rather than at the main current terminals, providing a well-defined measurement interval and reducing sensitivity to external wiring variations. This is particularly valuable in busbar assemblies where current distribution across wide conductors could otherwise introduce spatial measurement uncertainty.
The TCR of less than ±100ppm/°C bounds the resistance change to a narrow window across the full operating range, keeping current measurement accurate without elaborate thermal correction. The 1000-cycle temperature shock qualification, resistance-to-solvent rating, and 1000-hour operational life test confirm readiness for industrial assembly processes and demanding field environments. At 0.05mΩ and 840A continuous rating, the TCS8440T is positioned for high-current applications where minimising insertion voltage drop and power dissipation is as important as measurement precision.
TCS8440T Current Sensing Resistors Specifications
A practical overview for engineers and procurement teams evaluating resistive solutions.
Model: TCS8440T
Resistor type: AEC-Q200 E-beam
Description: E-beam welded shunt
Power Rating: 36W
Rated Current: 840A
Resistance (Ω): 0.05m
Tolerance (%): ±1, ±2, ±5
TCR (ppm/C): 100
Applications of the TCS8440T Current Sensing Resistors
Where RARA metal clad resistors are deployed in the field.
Battery charging current control in automotive and hybrid electric vehicle electronics — monitoring charge and discharge currents in traction battery packs with minimum resistive loss.
Hybrid electric vehicles (HEVs) and fuel cell systems — Kelvin shunt measurement of high traction or stack currents where the voltage drop across the shunt must be minimised.
Current detection in precision power supplies — providing accurate feedback for regulated and constant-current output stages.
Industrial power conversion circuits — current sensing in motor drives, inverters, and DC-DC converters for closed-loop control and protection.
Constant electronic load equipment — precise current measurement to maintain regulated loading in test and burn-in systems.
High pulse power circuits — handling repetitive transient overloads without resistance drift in switched-mode and pulsed-load applications.
Renewable energy systems — current measurement in solar inverters, energy storage converters, and grid-tie equipment.
Telecommunications and data centre power infrastructure — high-current distribution monitoring in 48V and higher-voltage bus architectures.
Related Products of the TCS8440T Current Sensing Resistors
Model: TCS8536
Resistor type: AEC-Q200 E-beam
Description: E-beam welded shunt
Power Rating: 36W
Rated Current: 600~1200A
Resistance (Ω): 0.1m, 0.05m, 0.025m
Tolerance (%): ±1, ±2, ±5
TCR (ppm/C): 100
Model: PCBS
Resistor type: AEC-Q200 PCB+shunt
Description: Current sensing module
Rated Current: 350~1000A
Resistance (Ω): 25u, 50u, 100u
Tolerance (%): ±5
TCR (ppm/C): 100
Model: ECS
Resistor type: AEC-Q200
Description: Chip shunt
Power Rating: 1W~15W
Resistance (Ω): 0.2~10m
Tolerance (%): ±1, ±2, ±5
TCR (ppm/C): 100-200
Model: TCS
Resistor type: AEC-Q200 E-beam
Description: Shunt
Power Rating: 12W~36W
Rated Current: 200~350A
Resistance (Ω): 0.05~0.5m
Tolerance (%): ±1, ±2, ±5
TCR (ppm/C): 100
Why Choose RARA Current Sensing Resistors
What sets RARA apart for engineers and procurement managers in industrial and automotive markets.
01
8 Sub-Categories
No other single supplier covers AEC-Q200 chip shunts, milliohm precision types, four-terminal Kelvin shunts, power metering, and 12,000A panel shunts under one ISO-certified roof.
02
Extreme Precision
HPS, UHPS, and PSS precision shunts deliver ±0.05% tolerance and 3 ppm/°C TCR — meeting the accuracy demands of EV battery coulomb counting, precision power analyzers, and billing-grade energy metering.
03
Automotive Qualified
Multiple AEC-Q200 certified models (BCS, LRA, ECS, BWR, TCS, PCBS) with IATF 16949 manufacturing certification — covering EV battery management, motor control, and charging applications.
04
Global Track Record
Trusted by Tesla, GM Korea, Proterra, Siemens, Rockwell, and Schneider Electric — deployed in EV powertrains, industrial drives, and utility metering systems across six continents.
