GDM-8261A User Manual
224
[ 10 ] All speeds need Fixed range and Trigger Delay=0.
Frequency and Period Characteristics
Frequency Period
[3] [7]
Range
[2]
Frequency
24 Hour
[1]
23
˚
C±1
˚
C
90 Day
23
˚
C±5
˚
C
1 Year
23
˚
C±5
˚
C
Temperature
Coefficient/
˚
C
[5]
100 mV
to
750 V
[4]
3Hz - 5Hz
0.1
0.1
0.1
0.005
5Hz - 10Hz
0.05
0.05
0.05
0.005
10Hz - 40Hz 0.03
0.03
0.03
0.001
40Hz - 300kHz 0.006
0.01
0.01
0.001
Accuracy Specifications: ± % of reading
Measuring Characteristics
Frequency and
Period
Measurement
Method:
Reciprocal-counting technique. AC-coupled
input using the ac voltage measurement
function.
Voltage Ranges 100 mVrms full scale to 750 Vrms. Auto or
manual ranging.
Settling
Considerations
Errors will occur when attempting to measure the frequency
or period of an input following a dc offset voltage change.
The input blocking RC time constant must be allowed to
fully settle (up to 1 sec) before the most accurate
measurements are possible.
Measurement
Considerations
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.
Operating Characteristics
Function
Digits
Readings/s
[6]
Frequency,
Period
6 ½
1
5 ½
10
4 ½
100
[ 1 ] Relative to calibration standards.
[ 2 ] 20% overrange on all ranges, except 750 Vac.
[ 3 ] Input > 100 mV. For 10 mV to 100 mV inputs, multiply % of reading
error x10.
[ 4 ] 750 Vac range limited to 100 kHz
[ 5 ] 0
˚
~18
˚
C & 28
˚
~55
˚
C
