Siemens S5-135U/155U appendix LEDs for Fault Indication Signaling

CPUs, Memory Cards, Memory Submodules, Interface Submodules

LEDs for Fault

Indication and

Signaling

QVZ LED
on	During direct access or process image update, a module
	addressed by the program no longer acknowledges although
	S either it has acknowledged in single processor operation
	upon reset of the CPU 928 in the area of the process
	image (IB 0 to 127, QB 0 to 127) and has been entered as
	present in the ª9th trackº (see Programming Guide,
	CPU 928),
	S or it has been entered in DB 1 (address list) in
	multiprocessor or single-processor operation and has been
	recognized as present during the reset.
	Possible causes
	S Module failure.
	S Module was pulled out during operation, in the stop state
	or in the Off state without a subsequent reset.
ADF LED
on	The user program has referenced an I/O address under which
	no module is inserted.
ZYK LED
on	The maximum cycle time has been exceeded.
BASP LED
on	Command output is inhibited and the digital outputs will be
	directly switched to the safe state.

A detailed description of interrupt and error handling can be found in the

CPU 928 Programming Guide.

System Manual	5-59
C79000-G8576-C199-06