Chapter 6 Command Reference 191
LFREQ
Syntax LFILTER [control]
control
The control parameter choices are:
Power-on control = OFF.
Default control = ON.
Remarks • Level filtering can be used when level triggering for DC voltage, direct- and
sub-sampling. The level filter can also be used to reduce sensitivity to noise for
frequency and period measurements or when making AC or AC+DC voltage
measurements using the synchronous method (SETACV SYNC command).
• Query Command. The LFILTER? query command returns the present level
filter mode. Refer to "Query Commands" near the front of this chapter for more
information.
• Related Commands: DCV, DSAC, DSDC, FREQ, LEVEL, NRDGS, PER,
SETACV, SYNC, SLOPE, SSAC, SSDC, SSRC, TRIG
Example OUTPUT 722;"LFILTER ON" !ENABLES THE LEVEL FILTER
LFREQ
The LFREQ command allows you to specify the A/D converter's reference
frequency or measure the line frequency and set the reference frequency to the
measured value.
Syntax LFREQ [frequency]
or
LFREQ LINE
frequency
Allows you to specify the reference frequency. The valid range for the frequency
parameter is 45 - 65 Hz, or 360 - 440 Hz. When you specify a frequency in the
range of 360 - 440Hz, the multimeter divides that value by 8. For example, if you
specify LFREQ 400, the multimeter sets the reference frequency to 400/8 = 50Hz.
Power-on reference frequency = rounded value of 50 or 60Hz (see first Remark
below).
control
parameter
Numeric
Query
Equiv. Description
OFF 0 Disables the level filter; no filtering is done
ON 1 Enables the level filter