Frequency Counter Sensitivity And Trigger Levels; Input Characteristics; Min Max Recording - Fluke 28 II Ex Calibration Information Manual

28 II Ex
Calibration Information

Frequency Counter Sensitivity and Trigger Levels

Input Range
600 mV dc
600 mV ac
6 V
60 V
600 V
1000 V
Duty Cycle (Vdc and mVdc)
[1] 0.5 Hz to 200 kHz, pulse width >2 μs. Pulse width range is determined by the frequency by the frequency of the signal.
[2] For 6 V dc range, accuracy is unspecified.

Input Characteristics

Overload
Function
Protection

1000 V rms

1000 V rms

1000 V rms
Ω
1000 V rms

1000 V rms

MIN MAX Recording

Nominal Response
100 ms to 80 %
(dc functions)
120 ms to 80 %
(ac functions)
250 μs (peak)
[1] For 6 V range: 1 ms
8
Minimum Sensitivity (RMS Sine Wave)
5 Hz – 20 kHz
70 mV (to 400 Hz)
150 mV
0.3 V
3 V
30 V
100 V
Range
[1]
0.0 % to 99.9 %
Input
Impedance
(nominal)
10 MΩ <100 pF
10 MΩ <100 pF
(ac-coupled)
Open Circuit
Test Voltage
<7.0 V dc
<7.0 V dc
Specified accuracy ±12 counts for changes >200 ms in duration
Specified accuracy ±40 counts for changes >350 ms and inputs >25 % of range
Specified accuracy ±200 counts for changes >250 μs in duration
[1]
(add ±100 counts for readings over 6000 counts)
(add ±100 counts for readings in Low Pass mode)
0.5 Hz – 200 kHz
70 mV (to 400 Hz)
150 mV
0.7 V
7 V (≤140 kHz)
70 V (≤14.0 kHz)
200 V (≤1.4 kHz)
Within ± (0.2 % per kHz + 0.1 %) for rise times <1 μs.
Common Mode
Rejection Ratio
(1 kΩ unbalance)
>120 dB at dc, 50 Hz
or 60 Hz
>120 dB at dc, 50 Hz
or 60 Hz
>60 dB, dc to 60 Hz
Full Scale Voltage
5 MΩ or
600 Ω
To 6 MΩ
60 nS
<1.7 V dc <1.9 V dc 500 μA 100 μA 10 μA
2.200 V dc
Accuracy
Approximate Trigger Level
(DC Voltage Function)
40 mV
-
1.7 V
4 V
40 V
100 V
Accuracy
Normal Mode Rejection
>60 dB at 50 Hz or 60 Hz
>60 dB at 50 Hz or 60 Hz
Typical Short Circuit Current
6 kΩ 60 kΩ 600 kΩ 6 MΩ 50 MΩ
1 μA 0.4 μA 0.2 μA
1.0 mA typical
[2]