The PSB ultra-precision power shunt resistor series from Alpha Electronics offers 4-terminal (Kelvin) connections for current sensing and a power rating of up to 40W on a heat sink or 12W in free air (at +25°C) all with a low ohmic resistance range from 0.001Ω to 1Ω. By utilising Alpha’s Bulk Metal® foil resistor technology, they are able to offer excellent temperature characteristics with low temperature coefficients down to ±5 ppm/°C between the resistance range 0.005Ω and 1Ω.
Ultra-precision power shunt resistor
Available in any resistance between 0.001Ω and 1Ω
4-terminal (Kelvin) connection high power shunt
High heat dissipation due to aluminium-clad construction with fins
Power rating of 40W on a heat sink or 12W in free air at +25°C
Tolerances as low as ±0.1% over the whole resistance range
Tight TCR available of ±5 ppm/°C between 0.005Ω and 1Ω
Maximum working current of 100A
Maximum rated operating temperature +25°C
Temperature range from -55°C up to +85°C
The PSB ultra-precision shunt resistor series exhibits excellent temperature characteristics thanks to Alpha’s Bulk Metal® foil resistor technology, making them suitable for the most demanding precision and high power applications.
The 4-terminal connections of this high power shunt series offers accurate current sensing capabilities even in low extremity of resistance.
The PSB series has been designed for easy mounting to heat sink or water-cooled radiator as well as with threaded holes to fix cables with screws (Caution: please screw current terminals >5N·m and voltage terminals >1N·m)
Their 4-terminal design and high precision make them ideal for current sensing in precise power supply or motor driver applications.
The below table gives a summary of the specifications and options available for the Alpha PSB series:
* Thermal resistance of the heat sink 1°C/W
Available to use higher rated power with elevation of cooling effect
Please keep temperature of element surface less than +60°C
Alpha Manufacturing and Product Information
Alpha Electronics manufacturing process, adjustment of resistance value construction, and temperature characteristics of resistance information
We are pleased to provide you with a range of videos, please see below for the latest content available:
VIDEOS
Resistor Stability Put to the Test (Demo Video)
In this video, our host Richard Zuratt puts the stability of the three major resistor technologies — foil, thin, and thick film — to the test. Each resistor type is subjected to an overload pulse and its change in resistance value is recorded. Due to the homogeneous nature of the VPG Bulk Metal® Foil resistor, it is the only of the three to experience no change from the high power pulse. This demonstrated performance makes foil resistors the technology of choice for critical applications where long-term stability and survivability are paramount.
Advantages of Using Bulk Metal® Foil Resistors in High-Humidity Environments
All resistors that are based on nichrome, which is a category that includes both thin film devices and Bulk Metal Foil resistors, are susceptible to electro-chemical corrosion or etching when placed in a high humidity environment and powered with a very low wattage. But since the nichrome element of a Bulk Metal Foil resistor is hundreds of times thicker than the element in a thin film device with the same value, it will last much longer under these conditions. This video shows the actual etching process and survival times for thin film and foil nichrome resistive elements as they are tested in 100% humidity conditions.
Comparison Testing of Chip Resistor Technologies Under High Vibration
Surface-mount resistors suffer physical stresses when exposed to high vibration or thermally unstable environments. Failure modes commonly occur in welds, solder joints, connectors, and terminations, ultimately resulting in circuit failure. In this demonstration, vibration-table-mounted boards are subjected to ±2° deflection 25 times per second and monitored for any ΔR > 0.1%. All the chip resistors failed in 2 to 12 minutes (8K to 16K cycles). But the Alpha MPP molded Bulk Metal® Z-Foil resistor with flexible terminations experienced over a million cycles with no change in resistance.
VIDEOS
Resistor Stability Put to the Test (Demo Video
In this video, our host Richard Zuratt puts the stability of the three major resistor technologies — foil, thin, and thick film — to the test. Each resistor type is subjected to an overload pulse and its change in resistance value is recorded. Due to the homogeneous nature of the VPG Bulk Metal® Foil resistor, it is the only of the three to experience no change from the high power pulse. This demonstrated performance makes foil resistors the technology of choice for critical applications where long-term stability and survivability are paramount.
Advantages of Using Bulk Metal® Foil Resistors in High-Humidity Environments
All resistors that are based on nichrome, which is a category that includes both thin film devices and Bulk Metal Foil resistors, are susceptible to electro-chemical corrosion or etching when placed in a high humidity environment and powered with a very low wattage. But since the nichrome element of a Bulk Metal Foil resistor is hundreds of times thicker than the element in a thin film device with the same value, it will last much longer under these conditions. This video shows the actual etching process and survival times for thin film and foil nichrome resistive elements as they are tested in 100% humidity conditions.
Surface-mount resistors suffer physical stresses when exposed to high vibration or thermally unstable environments. Failure modes commonly occur in welds, solder joints, connectors, and terminations, ultimately resulting in circuit failure. In this demonstration, vibration-table-mounted boards are subjected to ±2° deflection 25 times per second and monitored for any ΔR > 0.1%. All the chip resistors failed in 2 to 12 minutes (8K to 16K cycles). But the Alpha MPP molded Bulk Metal® Z-Foil resistor with flexible terminations experienced over a million cycles with no change in resistance.
