Agilent Technologies 34980A Service Manual page 50

2
Specifications
Internal DMM Measurement Characteristics (continued)
Frequency and period
Measurement method
Voltage ranges
Gate time
Measurement time-out
Measurement Consideration
DC Current
Shunt resistance
Input protection
True RMS AC current
Measurement method
Shunt resistance
Input protection
Thermocouple
Conversion
Reference junction type
Open thermocouple check
Thermistor
RTD

Measurement noise rejection 60 (50) Hz
[1]
DC CMRR
AC CMRR

Integration time
200 plc/3.33 s (4 s)
100 plc/1.67 s (2 s)
20 plc/333 ms (400 ms)
10 plc/167 ms (200 ms) 
2 plc/33.3 ms (40 ms)
1 plc/16.7 ms (20 ms)
< 1 plc
[1] 
For 1 k unbalance in LO lead
[2]
For power line frequency ±0.08%
[3]
For power line frequency ±1% use 75 dB or ±2.5% use 60 dB
34
Reciprocal counting technique
Same as AC voltage function
1s, 100 ms, or 10 ms
Selectable 3 Hz, 20 Hz, 200 Hz LF limit
All frequency counters are susceptible to error when
measuring low-voltage, low-frequency signals.
Shielding inputs from external noise pickup is
critical for minimizing measurement errors.
5 for 10 mA, 100 mA; 0.1  for 1 A
1A 250 V fuse on 34921A module
Direct coupled to the fuse and shunt. AC coupled
True RMS measurement (measures the ac component
only).
5  for 10 mA; 0.1  for 100 mA, 1 A
1A 250 V fuse on 34921A module
ITS-90 software compensation
Internal, fixed, or external
Selectable per channel. Open > 5 k
44004, 44007, 44006 series
 = 0.00385 (DIN) and  = 0.00392
140 dB
70 dB

[2]
Normal mode rejection
[3]
105 dB
[3]
100 dB
[3]
95 dB
[3]
90 dB
85 dB
60 dB
0 dB
34980A Service Guide