Measurement Options
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displayed offset becomes the reference value. Subtracting the offset from the actual input, the display
will be as follows:
Displayed reading = Actual Input – Reference
Selecting a range that cannot accommodate the relative value does not cause an overflow condition, but
it also does not increase the maximum allowable input for that range. For example: on the 1.2 V range,
the meter still overflows for a 1.4 V input.
To set a REL value, press
when the display shows the value you want as the relative value. The
REL annunciator will display. To disable REL, Press
again.
You can also input a REL value manually using the mX+b function. Set M for 1 and B for any value you
want. Please refer to Chapter 3 for details about mX+b function.
4.1.4 Rate
The RATE operation sets the integration time of the A/D converter, the period of time the input signal is
measured. The integration time affects the usable digits, the amount of reading noise, as well as the
reading rate of the instrument. The integration time is specified in parameters based on a number of
power line cycles (NPLC), where 1 PLC for 50 Hz is 20 msec.
In general, the fastest integration time (FAST (0.1 PLC) set from the front panel or remote interface)
results in increased reading noise and fewer usable digits, while the slowest integration time (10 PLC)
provides the best common-mode and normal-mode rejection. In-between settings are a compromise
between speed and noise.
The RATE parameters are explained as follows:
Fast
FAST sets integration time to 0.1 PLC. Use FAST if speed is of primary importance, however it is at the
expense of increased reading noise and fewer usable digits.
Medium
Medium sets integration time to 1 PLC. Use Medium when a compromise between noise performance
and speed is acceptable.
Slow
Slow sets integration time to 10 PLC. SLOW provides better noise performance at the expense of speed.
For the AC functions (ACV, ACI), Rate setting determines the bandwidth setting as below:
Fast
500 Hz~100 kHz
Medium
50 Hz~100 kHz
Slow
5 Hz~100 kHz
Note:
The integration time can be set for any measurement function except frequency, period,
continuity (FAST) and diode test (MEDium). For frequency and period, it is the equivalent
of the gate time, 1 sec.
