&RPPLVVLRQLQJ
S7-300 Automation System, Hardware and Installation: CPU 31xC and CPU 31x
A5E00105492-03
9-13
5HVHWWLQJ0HPRU\YLDWKH0RGH6HOHFWRU6ZLWFKRIWKH&38
:KHQGR\RXUHVHW&38PHPRU\"
You must reset CPU memory,
• Before you download a (completely) new user program to the CPU
• If the CPU requests memory reset with its STOP LED flashing at 0.5 Hz
intervals Possible reasons for this request are listed in the table below .
Table 9-3 Possible causes for the CPU memory reset request
&DXVHVRID&38UHTXHVWWRUHVHW
PHPRU\
5HPDUNV
The MMC has been replaced -
RAM error in CPU -
The main memory is too small, that is,
all blocks of the user program on an
MMC cannot be loaded.
Attempts to load faulty blocks; e.g. if
the wrong instruction was
programmed.
CPU with MMC inserted: A further memory reset
is requested.
Additional information on MMC behavior after a
memory reset can be found in the &38'DWD
Reference Manual, 0HPRU\FRQFHSWchapter.
+RZWRUHVHWPHPRU\
There are two ways to reset CPU memory:
0HPRU\UHVHWZLWKWKHPRGHVHOHFWRU
VZLWFK
0HPRU\UHVHWZLWK3*
... is described in this Chapter. ... only possible if the CPU is in STOP mode
(see 67(32QOLQH+HOS).
&38PHPRU\UHVHWZLWKWKHPRGHVHOHFWRUVZLWFK
The table below shows the steps required for resetting CPU memory.
Table 9-4 Procedure for resetting the CPU memory
6WHS 5HVHWWLQJ&38PHPRU\
1. Turn the key to STOP position
2. Turn the key to MRES position. Hold the key in this position until the STOP LED
lights up for the second time and remains on (this takes 3 seconds). Then
release the key.
3. You must turn the key to MRES position again within 3 seconds and hold it
there until the STOP LED flashes (at 2 Hz). You can now release the switch.
When the CPU has completed memory reset, the STOP LED stops flashing and
remains lit.
The CPU has reset the memory.
To Next Page
Loading...
Need help?
General
