Instruction manual

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The following ASCII string will program the phase A output to 0 degree relative to the external
sync input and select the external sync mode.
PHZA0 SNC EXT
Sending the ASCII string SNC INT will disable the sync input.
3.7.5.7.DROP CYCLE (DRP)
The DRP header is used to identify the Drop Command. The argument is a numeric data field
from 1 to 5. The following string will drop the output voltage for phase B for five complete
cycles and start at 0 degree of the wave form
PHZ 0 DRP B 5
3.7.5.8. CALIBRATION (CAL)
The CAL header when used alone or followed by the header AMP, in addition to an A, B or
C extension, is used to callibrate the programmed output voltage. The argument is a relative
starting coefficient from 0 to 255 or the ASCII # symbol. The CAL ramp is terminated with
the GPIB message Group Execute Trigger (GET). The CAL header can be used with a
Delay (DLY) command to allow the external calibrtion AC DVM time to settle. Refer to
Section 4 for addititonal information.
A CAL coefficient can be programmed without a ramp by using only the argument with the
CAL header.
To program the CAL A coefficient to 55, use the following string:
CALA55
To calibrate pahse A at 135 volts, start the CAL routing witha GPIB GET meassage with the
CAL coefficient starting at 20 and with each step lasting 2 sconds, use the following string:
AMP135.0 CALA20 DLY2 STP1 VAL255 TRG
In this example the output will program to 135.0 and start to change the output by stepping
the CAL value after a “GET: message. The ramp will terminate after a second “GET”
message.
The following example will calibrate the phase A output by starting the ramp with the
existing CAL coefficient and reducing the output with the steps lasting one second: