34410A AGILENT TECHNOLOGIES, 34410A Datasheet - Page 13

• Manufacturer Part Number: 34410A
• Description: MULTIMETER, DIGITAL, BENCH, 6-1/2 DIGIT
• Manufacturer: AGILENT TECHNOLOGIES

Specifications of 34410A

• Dmm Type: Bench
• Voltage Measuring Range Dc: 100mV To 1000V
• Voltage Measuring Range Ac: 100mV To 750V
• Current Measuring Range Dc: 100µA To 3A
• Current Measuring Range Ac: 100µA To 3A
• Lead Free Status / RoHS Status: na

Understanding Fast Measurements
Some of the examples in
the previous section require
programming the DMM to its
fastest measurement settings
and using the trigger subsystem.
Depending on the requirements
of your application, the fastest
rate may not achieve the desired
performance. For example, if
measurements are made with
an aperture less than 1 PLC
and in the presence of signifi-
cant power-line frequency
interference, there is no normal
mode rejection (NMR) at those
frequencies. Any rejection of
such interference would have
to occur through averaging
readings in the computer, and
many samples must be taken
over the period of the noise to
reject. To sample faster than
1 PLC in the presence of noise,
the typical solution is to add
passive filtering to the sensors
before they are measured by
the DMM.
Resolution also can be reduced
when you are making fast
measurements. For the 34410A
and 34411A, the reduction is
based on noise performance of
the A-to-D and input circuits.
All DMMs have such noise in
varying degrees. The 34410A
Figure 9. The entire measurement speed
spectrum of the 34410A and 34411A DMMs
and 34411A have industry-
leading performance in
measurement speed versus
RMS noise. The chart in Figure 9
shows the entire measurement
speed spectrum of both DMMs,
from 0.001 NPLC (50 k read-
ings/s) to 100 NPLC.
This chart represents straight-
through signal processing – the
10 V range. The following table
shows how noise affects resolu-
tion of different measurement
functions.
Operating Characteristics
Maximum readings/second
Function
DCV
2-wire
DCI
ACV
ACI
Frequency
Period
0.01
100
0.1
10
0.001
1
Ω
0.01
4.5
50 k
25 k
3 k
500
500
450
450
Integration Time (NPLC)
0.1
13
Digits
5.5
10 k
3 k
60
500
150
90
90
1
10
6.5
1 k
60
60
150
150
10
10
100
For the 34411A, note that 50 k
readings/s is specified at 4.5
digits for DCV, but it is only 3 k
readings/s with DCI. A speed
reduction is also recommended
and occurs with resistance
measurements. This does not
limit measuring current or
resistance at 50 k readings/s.
It simply means that Agilent
has chosen to show readings
rates only for the 4.5, 5.5,
and 6.5 digits resolutions. In
applications like automotive
electronic test, 3.5 or 4 digits
of resolution may be more
than adequate, so higher
sample rates are useful.
One way to make faster, higher-
resolution DCI measurements
at guaranteed higher resolution
is to use an external current
shunt and sample the shunt
resistor using DCV at 50 k
readings/s. A 1-ohm resistor
gives 0.001 V at 1 mA, so very
precise measurements can be
made at high resolutions.