Programming Examples 5Keysight Models 6811C, 6812C, and 6813C Programming Guide 233Programming the output phaseYou can control the phase of the AC voltage waveform relative to an internalreference with:PHASe which sets the phase in degrees. If is positive, the voltage waveform leads theinternal reference.In the single-phase models, the only discernible effect of using the PHASecommand is to cause an instantaneous shift in output waveform phase. This isbecause the internal phase reference is not accessible externally.Current limitAll ac source models have a programmable rms current limit function. Thecommand to set this limit is:CURRent where is the rms current limit in amperes.If the load attempts to draw more current than the programmed limit, the outputvoltage is reduced to keep the rms current within the limit. Since the rmsdetection involves a filter time constant that is long compared to a single outputcycle, the response time of the rms current limit is not instantaneous. When theoutput voltage is reduced, its waveform is preserved (the output waveform isattenuated, not clipped).The ac source can be programmed to turn off its output if the rms current limit isreached. This protection feature is implemented with theCURRent:PROTection:STATe command as explained in Chapter 3, "LanguageDictionary".Peak current limitThe Keysight 6811C, 6812C, and 6813C have a programmable peak current limitwhich limits the instantaneous current. The command to set this limit is:CURRent:PEAK where is the peak current in amperes.Since instantaneous current tends to be highest when the output voltage ishighest, this current limit tends to clip the peaks of the output voltage waveform.
