Measurements International’s (MI) series of Shunt Measurement Systems offers the best accuracy and lowest uncertainty of any commercial system available on the market today. The MI High Current Range Extenders expand the measuring capabilities of the MI model 6010 and MI 6242 to measure lower resistance values at higher currents.
The MI 6010 and 6242 series of Shunt Measurement Systems provide the widest range with the lowest uncertainty of any manufacturer. System accuracy: < 2 ppm compared to 15 ppm from our nearest competitor.
Measurements International is the original manufacturer of the Automated Resistance Measurement System. With the most current comparator experience in the industry, Measurements International Shunt Measurement Systems are designed using sound metrology principles.
The MI series of 6010 Bridges and Shunt Measurement Systems are used by the majority of National Measurement Laboratories and military labs worldwide as well as the US Air Force, US Army and US Navy.
The new series of MI 6010 and 6242 systems are the only self-calibrating Bridge systems in the world. For years, users would only perform interchange measurements at 1:1 ratios. 6010 and 6242 series Bridges are commonly being used worldwide to calibrate other manufacturer’s Bridges and Shunt Measurement Systems.
While other manufacturers require the use of more than 50 coefficients to correct for systematic hardware errors in their bridges, MI Bridges require no corrections. Other manufacturers also claim to have the best accuracy and meet the military requirements for resistance measurements yet are unable to compare to Measurements International.
Don’t be fooled or misled by other manufacturers’ claims, ask for references and consult any NMI in regards to modern resistance measurement systems.
|Ratio Range||Resistance||Max Current||Accuracy|
Standard resistors of 1 Ω, 10 Ω and 100 Ω may also be used to extend the ratio for higher currents. For example, if you had a 0.01 Ω shunt at 100 A it could be measured on the 100 A range using a 10 Ω standard or if you had a 0.1 Ω shunt at 15 A you can measure it on the 100 A range using a 100 Ω standard.
All of the MI High Current Shunt Measurement systems have the capability of providing both the resistance/temperature curve as well as the time/temperature curve for the shunt being measured, a feature that only MI offers. The resistance temperature curve is found by measuring the shunt at several different current levels and plotting the equilibrium points. This type of curve determines the characteristics of the shunt when the heat is dissipated by the shunt elements and is modelled by a second-order polynomial. Equilibrium is obtained when the temperature and resistance of the shunt reach a steady state at the current level being measured. Once the resistance/temperature equilibrium curve has been established the shape will not change, but the resistance will drift as does a typical resistance standard.
In addition, environmental temperature, pressure and humidity can be measured and logged with shunt data.
6511 DCC Range Extender with Built-in Power Supply
The 6511 was designed for users that do not require high currents but still need the best accuracy for their measurements. Three (3) ratios of 10, 100 and 1000 and a built-in linear power supply of 10 A are provided for the measurements of 0.1 Ω, 0.01 Ω and 0.001 Ω current resistors or shunts. The maximum output current of the 6511 is 100 mA for ratios 10 (1 A) and 100 (10 A) and 10 mA for ratio 1000 for 10 A in.
6011/150 A DCC Range Extender
The 6011 is a precision DC Current Range Extender for currents up to 150 A. Using innovative technological improvements to the direct current comparator, the linearity specification has been improved to less than 0.01 ppm over its entire range. The 6011 can be used as a stand-alone unit for dividing high currents down to workable levels. The full-scale output current of the 6011 is 150 mA on all ranges. Applications include calibration of DC Current Sources and in DCC Shunt measurement systems.
The 6011/150 has a built-in reversing switch and automatic ranging of the 1, 10 and 150 A ranges. As a stand-alone unit, applications include calibration of DC current sources up to 150 A. All that is required is a DVM to measure the voltage across a standard resistor connected to the 6011 output and any power supply can be calibrated easily and efficiently.
|Currents||150 A||10 A||1 A|
|6011/100 Uncertainties||0.4 ppm||0.3 ppm||0.2 ppm|
When used in the shunt measurement system, the system can be automated using a controller and the model 6150A/150 DC Power Supply.
|6010/6011/150 Uncertainties||2 ppm||2 ppm||1 ppm||0.41 ppm||0.31 ppm||0.21 ppm|
Figure 1: Shunt Calibration
The system can be powered from a 100 V, 120 V, 220 V or 240 V single-phase supply. There is no requirement for special cooling or heat exhausts providing flexibility for room location. Mounted on wheels, the 6010/150 can be moved about easily when required.
When mounted in the rack, the shunt connection is made easily from the front of the rack. Installation and operation are easy when used with the 6010 or 6242 Resistance Bridges.
6011/300 DCC Range Extender
The 6011/300 is a precision DC Current Range Extender for currents up to 300 A. Using the same innovative technological improvements as used in the 6011/150 direct current comparator, the linearity specification has been improved to less than 0.01 ppm over its entire range. The full-scale output current of the 6010/300 system is 100 mA on all ranges.
The 6011/300 has a built-in reversing switch and automatic ranging of the 3 A, 30 A and 300 A. As a stand-alone unit, the 6011/300 can be used to calibrate DC Current Sources up to 300 A. All that is required is a DVM to measure the voltage across a standard resistor connected to the 6011/300 output and any power supply can be calibrated easily and efficiently.
|6011/300 Uncertainties||0.4 ppm||0.4 ppm||0.3 ppm||0.2 ppm|
When used in the 6010/300 Shunt Measurement System, the system can be automated using a controller and a model 6100A/300 DC Power Supply.
|6010/6011/300 Uncertainties||2 ppm||2 ppm||1 ppm||0.41 ppm||0.31 ppm||0.21 ppm|
The system can be powered from a 100 V, 120 V, 220 V or 240 V single-phase supply. There is no requirement for special cooling or heat exhausts providing flexibility for room location. Mounted on wheels, the 6010/300 can be moved about easily when required.
Figure 2: 6010/300 A Schematic
6011/1000/3000/5000 Shunt Measurement Systems
As a shunt measurement system, the 6010/1000/3000/5000 consists of a 6010/150 A module and the 6014/1000, 6014/3000 or 6014/5000 module. The system also features a built-in reversing switch and automatic ranging and is supplied in a rack on wheels for easy installation. The connection of the shunt is made at the side of the rack where two copper plates extend through the side panel. This effectively removes any heat loss due to poor connections to the shunt wires. In the high current shunt measurement system, the output current of the 6014 range extender (with a ratio of 1000:1) feeds directly into the 6011/150 A range extender as automatic ranging is performed inside the 6011/150 A. The 6011/150 A Range Extender is a precision DC Current Range Extender with ratios of 1000:1, 100:1 and 10:1. Used with the model 6014, ratios of 1,000,000:1 can be achieved.
For currents of 1000 A and higher, the system can be powered from a 240 V single-phase or 208/360 three-phase supply. The total power consumed is a result of the external load placed on the current sources. With a 2 V compliance, the power can be as high as 5000 A × 2 V = 6000 W if there are no losses in the leads. This type of power is high enough to raise the temperature in your calibration laboratory. As a result, MI recommends venting at the top of the rack directly into the ventilation system return to remove this heat from the laboratory if this is an issue.
Mounted on wheels the 6010/1000/3000/5000 can be moved about easily when required. Installation and operation are easy when used with the 6010 or 6242 Resistance Bridges.
Figure 3: 6010/5000 A Shunt Calibration System schematic
6010/1000 A/3000 A/5000 A Connections
The shunt is connected at the side of the rack where two copper plates extend through the side panel. This effectively removes any heat loss due to poor connections from using wires or cables to connect the shunt. In the high current shunt measurement system, the output current of the 6014M range extenders (with ratio of 1000:1) feeds directly into the 6011/150 A Range Extender as automatic ranging is performed inside the 6011/150.
Figure 4: Shunt Connections
Figure 4 shows a 3000 A shunt connected to the 6010/3000 A terminals. Copper bars are used to extend the 6010/3000 A bus connections so that there is no heat loss in the connections or copper bars. This yields lower standard deviations in the measurements and is far superior to using cables. These copper bars can be supplied as an option with MI shunts.
9332/3000 A Shunt/10 µΩ
Figure 5: 9332/3000 Thermal Image
Measurements International also manufactures a variety of shunts ranging from a 10 A (model 9332/10) to 3000 A (model 9332/3000/10 µΩ). These shunts are designed so that the current is evenly distributed across the plates. Figure 5 shows a 9332/3000 A shunt with a thermocouple under normal and thermal imaging.
MI provides the best uncertainties in a shunt measurement system and we offer a total solution in our 6010 or 6242 software. Not only does the software give you control to all the systems above, it can also be used to interface to temperature/humidity and pressure modules for recording these parameters at the time of measurement. Data from all the measurements are stored into a text file which can be easily imported to Excel for plotting both the shunt value and temperature/resistance curves for the shunt. Features of the software include the following:
|Model 4200 Series Matrix Scanners
An efficient method of reducing the cost of calibration, models offer 10-, 16-, and 20-channels with either binding posts or wire inputs.
|Model 9400 Standard Resistor Oil Bath
A stable and quiet oil bath with a capacity of 80 litres used for the maintenance of oil resistors. The 9400 is Peltier cooled, GPIB controllable, and also available is the optional 16-channel interconnect panel.
|Model 9210 Primary Resistance Standard
Based on a specially treated evanohm alloy, and using a proprietary process to improve stability and temperature coefficient, the 9210A is the most stable resistor commercially available. The long term drift rate is better than 0.2 ppm per year and TC is less than 0.05 ppm/°C.
|Model 9300A Standard Resistor
GPIB controllable and uses solid-state cooling, the 9300A is a cost-effective means to maintain the temperature of up to 4 SR104’s or 15 model 9331 air resistors from 15 °C to 40 °C with stability < 15 mK. Ideal for establishing temperature coefficients.
|Model 9332 Current Shunts
The models 9332, DC Current Shunts are the latest development from Measurements International series of DC resistors and shunts.
Measurements International can supply custom high current cables capable of handling any amperage up to and
above 5000 A.