4 Using the Solar Array Simulator
76 Series E4360 User’s Guide
Table Resolution
When operating in Table mode, the voltage/current values are converted
into a DAC table used by the instrument to control the output. You have
a choice in the size of this DAC table to optimize your application for
either better table resolution or faster update speed. Refer to Curve
Resolution as previously described in this chapter for more information.
Front Panel Restrictions
You can use the front panel when the unit is operating in Table mode.
However, any Fixed-mode voltage and current values that you enter
from the front panel will have no effect on the unit while it is in Table
mode. The front panel values will take effect when the unit is placed in
Fixed mode. All other functions such as output On/Off, Menu, Meter,
Channel, and Error are active while the unit is in Table mode.
Data Logging Measurements
The measurement examples discussed earlier in this chapter are suitable
for low data rate applications. Data logging should be used in
applications requiring higher data rate from multiple instruments. Data
logging commands are not available from the front panel.
Data logging lets the SAS capture and buffer multiple measurements
and return the data as a group. Since multiple data is returned in one
transaction, this will dramatically increase the data bandwidth of the
system. Briefly, to make data logging measurements:
1. Select the pacing mechanism and time interval.
2. Select the trigger source.
3. Initiate the data logger.
4. Trigger the data logger.
5. Format and Fetch the measurements.
Data logging measurements are captured from the free-running data
stream (the same as the front-panel). The captured data are the
instantaneous voltage and current measurements.
Each data logging measurement consists of a voltage and current. The
fastest data logging rate is 50 measurements per second with a
minimum time interval of 20 ms. The slowest data logging rate is 1
measurement per 65.535 seconds with a maximum time interval of
65.535 seconds. The buffer size is 65,534 records. Each record has a
voltage and a current value. At the minimum time interval, the single-
shot logging time will be about 21 minutes. At the maximum time
interval, the logging time will be about 1192 hours.
Since data logging is de-coupled from the measurement system, explicit
triggered measurements and fetches can occur while the data logger is
running. However, since the free-running data stream is interrupted by
the triggered measurement request, the logged data may have a jitter of
1 measurement sample (about 1.7 ms).
To Next Page
Loading...
Need help?
General
