8½-Digit High-Accuracy DMMs for Calibration and Precision Measurement
The ADCMT 7481 and 7482 are 8½-digit precision digital multimeters designed for calibration laboratories, research and development, standards work, and high-accuracy inspection-system verification.
Both models provide up to 119,999,999 counts for DC voltage and resistance, with resolution down to 10 nV for DC voltage, 100 fA for DC current, and 1 μΩ for resistance measurement.
8½ Digits
Up to 119,999,999-count display
0.01 ppm
High-resolution precision measurement
5 ppm/year
DC voltage relative accuracy
50,000 rdgs/s
Maximum high-speed sampling
The 7481 and 7482 support DC voltage up to 1000 V, DC current up to 1 A, and resistance up to 1000 MΩ. A self-calibration function compensates internal errors caused by temperature changes and reduces the number of external standards required for calibration.
The 7482 adds True RMS AC voltage and current measurement as well as frequency and period measurement. Its AC voltage capability covers frequencies from 10 Hz to 2 MHz.
8½-Digit Precision Measurement
Measure DC voltage and resistance with up to 119,999,999 counts and resolution equivalent to 0.01 ppm.
Ultra-High Resolution
Achieve resolution down to 10 nV for DC voltage, 100 fA for DC current, and 1 μΩ for resistance measurement.
Self-Calibration
Internal self-calibration compensates measurement errors caused by temperature variation and supports high-accuracy operation over time.
Two-Standard External Calibration
Calibrate the primary DC ranges using only a 10 V voltage standard and a 10 kΩ resistance standard together with the internal self-calibration system.
Thermal EMF Cancellation
High-precision resistance measurement automatically cancels micro thermoelectric voltage that can otherwise introduce low-resistance errors.
DC Voltage Ratio Measurement
Measure a reference voltage through the 4-wire resistance terminals and calculate voltage ratio for attenuator, resistance, and power applications.
High-Speed Sampling and Memory
Acquire data at up to 50,000 readings per second and store 50,000 measurements internally, expandable to 500,000 with Option +06.
Comparator and Statistics
Perform PASS/FAIL comparison and calculate maximum, minimum, average, dispersion, and standard deviation across stored measurement data.
AC Measurement on 7482
The 7482 adds True RMS AC voltage/current measurement plus frequency and period measurement, including AC voltage from 10 Hz to 2 MHz.
Calibration laboratory reference measurement
Inspection-system calibration
Semiconductor production-system verification
Precision DC voltage measurement
High-accuracy resistance measurement
DC voltage ratio measurement
Precision electronic component testing
R&D and standards laboratory measurement
| Specification | 7481 | 7482 |
|---|---|---|
| Maximum Display | 119,999,999 | 119,999,999 |
| DC Voltage Measurement | 10 nV to 1000 V | 10 nV to 1000 V |
| DC Voltage Relative Accuracy | 5 ppm/year | 5 ppm/year |
| DC Current Measurement | 100 fA to 1 A | 100 fA to 1 A |
| Resistance Measurement | 1 μΩ to 1000 MΩ | 1 μΩ to 1000 MΩ |
| Resistance Relative Accuracy | 8 ppm/year | 8 ppm/year |
| AC Voltage Measurement | Not available | 100 nV to 700 V True RMS |
| AC Current Measurement | Not available | 100 pA to 1000 mA True RMS |
| AC Voltage Frequency Range | Not available | 10 Hz to 2 MHz |
| Maximum Sampling Rate | 50,000 readings/s | 50,000 readings/s |
| Internal Data Memory | 50,000; 500,000 with Option +06 | 50,000; 500,000 with Option +06 |
| Temperature Measurement | Available | Available |
| Interfaces | USB, GPIB; LAN optional | USB, GPIB; LAN optional |
