AMETEK Lx Series II - Manual (Page 100)

User Manual Lx / Ls Series II
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right can be programmed to the full 300 V rms as this still falls within the same peak voltage
limitation of the AC source.
If the Lx Series is used over the bus, the “:VOLT? MAX” query command can be used to
determine the maximum allowable RMS voltage for the selected waveform. Using the returned
value as part of a program will prevent range errors.
4.4.5 Frequency Response Restrictions
The user may create a waveform that contains any number of harmonic frequencies of the
fundamental. The AC Source itself however has a finite signal bandwidth and will attenuate
higher frequency components of the signal. To limit the maximum frequency component of the
output signal, the controller automatically applies a band-pass filter to all custom waveforms as
they are downloaded. The controller implements the following process for user-defined
waveforms:
Each down loaded waveform will have a computed frequency limit that is less than or equal the
maximum frequency limit of the AC source. The frequency limit is a function of the harmonics
content of the waveform and will follow the equation below.
Fmax
h
= Fmax/(level * h
n
)
If Fmaxh is below the minimum frequency limit, the waveform will be rejected at down load time
and the label will be deleted from the waveform catalogue.
If the Lx Series is used over the bus, the “:FREQ? MAX” query command can be used to
determine the maximum allowable fundamental frequency for the selected waveform. Using the
returned value as part of a program will prevent range errors.
Limits assume a program of full-scale voltage. No adjustments for voltage setting are made
below the full-scale value.
Waveform selection and frequency programming will be subject to the above limit. An error
message will be generated to reflect this type of error:
"22,Waveform harmonics limit"
Transient editing will also generate the above error during keyboard entry. Remote transient entry
will not check for the error until transient execution.
4.4.6 Switching Waveforms
Waveforms can be switched as part of the transient system. Each transient type setup menu has
a FUNC field. This field allows selection of any of the standard or custom waveforms available in
waveform memory. Refer to the section on transients for more details on using transient list to
switch output waveforms.