Keysight 34460A, Руководство по эксплуатации и обслуживанию

Страница: 310 / 583

l
Since the minimum value changes depending on configuration, a command order dependency exists.
You must completely configure the measurement before setting the sample timer to MIN, or you may
generate an error. A complete configuration includes such things as math statistics or scaling.
l
When using autorange, the MIN value is the recommended value, not the absolute minimum value.
With autorange enabled, MIN is calculated assuming a single range change will occur for every meas-
urement (not multiple ranges, just one range up or down per measurement). You can specify an <
inter-
val
> between the absolute minimum (assumes no range changes) and the recommended MIN value,
but it may generate a timing violation error when making measurements. Applying a value less than
the absolute minimum will generate an error.
l
To determine the absolute minimum value for the present configuration, set the sample time to 20 µs
(which may generate a settings conflict error), then read back the current sample timer value using the
SAMPle:TIMer? query. The sample source must be set to timer with a sample count or trigger count
greater than 1, for the settings conflict error to occur. The settings conflict error causes the timer to be
set to the absolute minimum value.
l
The sample time resolution is 1 µs, the aperture resolution is 2 us, and the actual hardware resolution
is not exactly 1 µs. There are cases where a sample time value, rounded to the nearest hardware res-
olution, will result in a smaller value than aperture when rounded to 2 µs. This will create error
-
221,"Settings conflict; cannot meet requested timing; SAMP:TIM changed" . For example, the fol-
lowing sequence of commands generates error -221 and sets the sample time to +2.00100000E-003.
*RST
FUNC "VOLT:DC"
VOLT:DC:APER 0.002
VOLT:DC:RANGE:AUTO OFF
VOLT:DC:ZERO:AUTO OFF
TRIG:DEL 0
TRIG:SOUR BUS
SAMP:COUN 2
SAMP:TIM 0.002
SAMP:SOUR TIM
This error can also occur if you attempt to set both values an odd number of µs. For example, setting
both values to 23 µs, generates error -221 and sets the sample timer to 24 µs.
l
After setting the sample count, source, and delay time, you must place the meter in the "wait-for-trig-
ger" state using the
INITiate or READ? command. A trigger is not accepted from the selected trigger
source (see TRIGger:SOURce command) until the instrument is in the "wait-for-trigger" state.
l
The interval may be set to any value from the absolute minimum described above to 3600 seconds.
However, the value is rounded to the nearest step. For dc measurements, the step size is 1 µs. For ac
measurements, it is ac bandwidth dependent.
l
The instrument sets the sample timer to 1 second after a reset ( *RST command) or an instrument pre-
set ( SYSTem:PRESet command).
See Also
TRIGger:COUNt
Keysight True
volt
Series Operating and Service Guide
311
SCPI Programming Reference