Datasheet

13
Electrical Specifications
AC + DC specifications for U1272A/U1273A and U1273AX
Function Range Resolution
Accuracy ± (% of reading + counts of least significant digit)
45 Hz to
65 Hz
20 Hz to
1 kHz
1 kHz to
5 kHz
5 kHz to
20 kHz
20 kHz to
100 kHz
True RMS
AC + DC
Voltage
1
30 mV 0.001 mV 0.7 + 40 0.8 + 45 1.1 + 45 1.1 + 60 3.6 + 60
300 mV 0.01 mV 0.7 + 25 0.8 + 30 1.1 + 30 1.1 + 45 3.6 + 45
3 V 0.0001 V 0.7 + 25 1.1 + 30 1.6 + 30 2.1 + 45 3.6 + 45
30 V 0.001 V 0.7 + 25 1.1 + 30 1.6 + 30 2.1 + 45 3.6 + 45
300 V 0.01 V 0.7 + 25 1.1 + 30 1.6 + 30 2.1 + 45 —
1000 V 0.1 V 0.7 + 25 1.1 + 30 1.6 + 30 — —
Function Range Resolution
Accuracy ± (% of reading +
counts of least significant digit)
Burden voltage/Shunt
45 Hz to 65 Hz 20 Hz to 2 kHz
True RMS
AC + DC
Current
2
300 µA 0.01 µA 0.8 + 30 1.1 + 30 < 0.04 V/100 Ω
3000 µA 0.1 µA 0.8 + 30 1.1 + 30 < 0.4 V/100 Ω
30 mA 0.001 mA 0.8 + 30 1.1 + 30 < 0.08 V/1 Ω
300 mA 0.01 mA 0.8 + 30 1.1 + 30
< 1.00 V/1 Ω
3 A 0.0001 A 0.9 + 35 1.3 + 35 < 0.1 V/0.01 Ω
10 A 0.001 A 0.9 + 35 1.3 + 35 < 0.3 V/0.01 Ω
1. Notes for voltage specifications:
• Overload protection: 1000 Vrms. For millivolt measurements, 1000 Vrms for short circuits with < 0.3 A current.
• Input impedance: 10 MΩ (nominal) in parallel with < 100 pF.
• For 20 to 100 kHz accuracy: Three counts of the LSD per kHz of additional error is to be added for frequencies > 20 kHz and signal inputs < 10%
of range.
• U1273AX only: For all AC+DC voltage ranges, the accuracy is specified at 2.5% + 30 counts when measuring below –20 °C for 20 to 45 Hz
AC+DC signals.
2. Notes for current specifications:
• Overload protection for 300 μA to 300 mA range: 0.44 A/1000 V; 10 × 35 mm 30 kA fast-acting fuse.
• Overload protection for 3 A to 10 A range: 11 A/1000 V; 10 × 38 mm 30 kA fast-acting fuse.
• Specification for 300 mA range: 440 mA continuous.
• Specification for 10 A range: 10 A continuous. Add 0.3% to the specified accuracy when measuring signals > 10 to 20 A for 30 seconds
maximum. After measuring currents > 10 A, cool down the multimeter for twice the duration of the measured time before proceeding with low
current measurements.
• U1273AX only: The accuracy for the 300 μA range, 3000 μA range, and 30 mA is specified after the Null function is used when measuring at
temperatures below –20 °C. The Null function is used to subtract the test lead resistance and thermal effect (by shorting the test leads).
• U1273AX only: For all AC+DC current ranges, the accuracy is specified at 2.5% + 30 counts when measuring below –20 °C for 20 to 45 Hz
AC+DC signals.