Error And Status Commands - TDK-Lambda GENESYS Series User Manual

11.8. Error and Status Commands

Any program that operates a remote power supply should routinely verify that the supply is
accepting commands as expected. There is always a chance that the program sent a
command incorrectly, the supply is set so a command cannot be carried out, or a fault
condition has shut down the supply. A reliable program will check for these errors.
There are three methods for checking the Genesys™ power supply status:

IEEE-488.2 Registers: these are a few simple registers in which a bit is set because of
a command error or instrument fault condition. The registers are read, set and cleared
using the Common Commands (these start with an asterisk).

SCPI Registers: these are an extension of the IEEE-488.2 registers. SCPI adds
registers which describe exactly what fault conditions occur in the power supply. It also
adds status registers that report operating modes during normal operation.

SYSTEM:ERROR Queue: This is a message-based error and status reporting system
where the status and error conditions are expressed in readable text. This is the
preferred method to verify commands are accepted.
11.8.1. Read System Error
This is query to read error messages from the power supply. It is recommended that
after any command is sent over the LAN, the SYSTEM:ERROR should be read to
verify the command is accepted. The SYSTEM:ERROR queue can also be set to
report faults which have shut-down the supply's output.
The SYSTEM:ERROR is a queue, or stack, that holds the last ten messages. The
first error message entered is the first one read. It is a good idea to read the
SYSTEM:ERROR queue regularly. When a faulty command is sent and the
SYSTEM:ERROR is read, the error message could relate to an earlier command.
The SYSTEM:ERROR queue may be cleared by:
 Sending the *CLS command (this also clears other registers)
 Sending the SYSTEM:ERROR:ENABLE command
 Reading the errors until the response is 0,"No error"
11.8.2. Read Power Supply Shut-Down Faults
Power supply shut-down faults will be reported by the SYSTEM:ERROR queue if the
STAT:QUES:ENAB 255 command is first sent (or a value other than 255, see
section 11.8.16 for bit descriptions).
If a fault is reported, then check for other faults by sending SYSTEM:ERROR? until the
response is 0,"No error"
Then, the event registers must be cleared by sending STAT:QUES? or *CLS. This
must be done before any more shut-down faults are reported by SYSTEM:ERROR?
For a multi-drop chain of supplies, these commands must be send to each
supply individually (see the INSTRUMENT:SELECT command in
section 12.4.1).
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