User manual
90 Relay Multiplexer Command Reference  Chapter 3 
SYSTem:ERRor?
SYSTem:ERRor? returns the error numbers and corresponding error 
messages in the error queue of a switchbox. See Appendix C for a listing 
of switchbox error numbers and messages.
Comments Error Numbers/Messages in the Error Queue: Each error generated by a 
switchbox stores an error number and corresponding error message in 
the error queue. The error message can be up to 255 characters long.
Clearing the Error Queue: An error number/message is removed from the 
queue each time the SYSTem:ERRor? command is sent. The errors are 
cleared first-in, first-out. When the queue is empty, each following 
SYSTem:ERRor? command returns +0, “No error”. To clear all error 
numbers/messages in the queue, execute the *CLS command.
Maximum Error Numbers/Messages in the Error Queue: The queue holds 
a maximum of 30 error numbers/messages for each switchbox. If the 
queue overflows, the last error number/message in the queue is replaced 
by -350, “Too many errors”. The least recent error numbers/messages 
remain in the queue and the most recent are discarded.
*RST Condition: *RST does not clear the error queue.










