KEPCO TMA 4882-27 - Manual (Page 51)

TMA4882-27 021910
A-5
A.15 *TST? — SELF TEST QUERY
*TST?
Syntax: *TST? Returned value: 0 or n (0 = pass test, n = fail test) where n = address of failed unit(s)
Description: Power Supply test.This query causes the power supply to do a self test and provide the controller
with pass/fail results. The *TST? command performs the following tasks on relay equipped units:
• Sets output off (disconnects Relays).
• Sets the output to a max positive level, measures the voltage reported to the A to D converter.
• Sets the output to 0, measures the output.
• Swaps the output relays to make the output negative.
• Sets the output to max negative level and measures the output.
• Set output to 0 and sets output relays to positive value.
For power supplies which do not have relays (e.g, MBT and BOP), the levels indicated above will actu-
ally appear at the power supply output.
Errors (e.g., voltage error or relay error) are reported over the Bit bus. These errors update flags in the
status Questionable register in the controller. If the power supply’s questionable register is 0, it is con-
sidered to have passed and if it is non-zero it has failed. An error on any power supply connected to
the controller is reported as the address of the power supply. if, for example, there are three power
supplies connected and *TST? is executed, all power supplies perform the test and the response will
be 0 if all pass. If device 2 fails, the response would be 2. If devices 2 and 3 fail the response would be
2,3.
The user can determine if there was a Relay error or a voltage setting error by sending STAT:QUESn?
to the device, replacing n with the number returned in response to *TST?. For example,
STAT:QUES1? should be sent if the *TST? response was a 1. A voltage error is reported in the ques-
tionable register if there is a problem in setting an output.
If the unit fails, it is recommended that the test be executed a second time after reading the
STAT:QUES register. This is recommended because if the error was already set in the status ques-
tionable register It is possible for a unit that fails *TST? may pass when retested.
A.16 *WAI — WAIT-TO-CONTINUE COMMAND
*WAI?
Syntax: **WAI Returned value: 0 or 1 (0 = pass test, 1 = fail test)
Description: Causes the power supply to wait until all previously issued commands and queries are com-
plete before executing subsequent commands or queries. This command can be used to guaran-
tee sequential execution of commands and queries. When all pending operations are complete (all
previous commands have been executed, changes in output level have been completed), the WAI
command is completed and execution of subsequent commands can continue.
Example:
FIGURE A-2. USING THE *WAIT-TO-CONTINUE COMMAND
VOLT 10;:*WAI;:volt 15 The *WAI command ensures that the power supply output
actually goes to 10V before being set to 15V