MI 6000B Automatic High Resistance Ratio Bridge

MI 6000B AUTOMATIC HIGH RESISTANCE RATIO BRIDGE

The MI 6000B is a fully automated bridge according to the Cutkosky Divider principle. This technology offers new solutions for measuring high-quality resistors more accurately and at lower currents. The Cutkosky or Binary Voltage Divider Technology solves all the errors normally associated with a DC comparator and at the same time offers significantly improved uncertainties. An internal monitoring circuit is used to monitor the measuring circuit. This protection can also be used to control the measuring leads, a monitored detector and resistance housings to increase effective isolation resistance and improve overall performance.

The system requires a stable voltage source (model 1000B) and a DVM detector (Fluke 8508A, Agilent 3458A, or Keithley 2000). Optimum performance is achieved with the Agilent 3458A as a monitored detector.

The 6000B model has a 4-channel matrix scanner with inputs R1, R2, R3 and R4. The number of inputs can be increased to 40 when the 6000B is used in combination with the 4200 series Low-Thermal Four-Terminal Matrix Scanners.

Calibration of the 6000B is simple and automatic. The calibration data is stored in a file for historical analysis. New calibration data is compared with the latest calibration data for the BVD’s tracking drift.

BINARY VOLTAGE DIVIDER

The principle of the 6000B Automated High Resistance Ratio Bridge is based on the Binary Voltage Divider (BVD). The reference to the BVD is supplied from a stable voltage reference, model 1000B. The model 1000B is a low-threshold, stable, low noise, programmable DC reference. The DC reference is connected to the rear of the 6000B source input terminals. The DVM detector with an input impedance of 10 GΩ or higher is used to measure the difference between the BVD output and the test voltage. An isolated monitoring circuit is provided to monitor the BVD and the DVM detector when performing the measurements. The monitoring voltage can also be used to drive the cans and/or shields of the tested resistors to reduce leakage problems between the housing and the resistor.

SYSTEM SOFTWARE AND APPLICATIONS

The 6000 SW of Measurements International controls all the above automatically. The software features report generation, historical analysis and the tracking and correction of resistance displacements. All measurement data is displayed in graph form as the measurement progresses. All uncertainties are calculated on 2 sigma’s.

For SR104 measurements the 6000 SW allows users to measure the temperature of the SR104. This is done using an external thermistor at the time of measurement. The thermistor is placed in the well of the SR104 and is measured against a 1 MΩ reference resistor. The 1 MΩ standard resistor is used to keep the current in the thermistor as low as possible in order not to cause self-heating. The software can then apply a correction for 23 °C or 25 °C.

The 6000B can also be used in combination with Measurements International’s 4200 series Matrix Scanners and 4220-1 interface adapter for the calibration of the SR1010 series Hamon resistor boxes.

COMBINING

In combination with the Measurements International model 9300 or 9300A Air Bath, alpha and beta calculations can be performed automatically on the tested resistors. You can export all data directly to Excel for different test patterns or mainframe applications. External air pressure, humidity and temperature indicators are optional and the entire system can be enclosed in a 4 or 6 ft. rack. Resistance baths (oil or air), instrument controllers, printers, system software, IEEE interface, installation and training are all available for complete system packages.