Workpoint window warning
Advanced Features
Note that the WHIGH and WLOW commands refer to both the voltage and current
thresholds.
Voltage mode example
Lets say that the Power Module in channel 1 is to be set to provide 12V with a current
limit of 10A. The voltage setting and, optionally, threshold values might be set using the
commands:
VSET 1,12
VHIGH 1,12.5
VLOW 1,11.5
For the current window thresholds we will have to consider the expected output current
that will be drawn by the load (remember: the Power Module will be operating in voltage
mode), because the thresholds can only be programmed above and below the set point.
If the expected output current is going to be 7A ± 1A, we will use the following
commands:
ISET 1,7
IHIGH 1,8.1
ILOW 1,5.9
ISET 1,10
Note that the last command is setting the output’s current limit value.
And lastly we will enable the window warning thresholds, using the commands:
WHIGH 1,1
and
WLOW 1,1
Using the
warnings
The following sections provide guidelines on how to utilize the workpoint window
warning mechanism.
Checking the status
Whenever an output value (output voltage or output current) goes outside of the defined
workpoint window the corresponding Power Module’s status bit (HV, HC, LV, LC) will
be set.
The most direct method of detecting a window warning is to read the Power Module’s
status structure (using the CSTS? Query) and examine the status and warnings registers.
However, this method involves routine and frequent checks of the Power Module’s status
thus loading the communication link and the controlling computer.
Using the events mechanism
The events generation masks
With a proper setup of the events generation masks (using the CMASK command) you
can instruct the Power Module to register window-warning events on the thresholds that
interest you. Furthermore, events can be generated on positive (value goes outside the
limits) and/or negative (value returns to the allowed range) transitions.
This way you can filter out the events that are of no interest to you and simplify the logic
of the governing software.
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XMP 2600 Programming Manual
rev. 1.1
