Siemens Simatic S7-300 CPU 31xC Series User Manual

Commissioning
8.4 Commissioning the Modules
S7-300, CPU 31xC and CPU 31x: Installation
8-8 Operating Instructions, Edition 08/2004, A5E00105492-05
Inserting/replacing the Micro Memory Card (MMC)
1. Switch the CPU to STOP mode.
2. Is an MMC already inserted?
If yes, ensure that no write operations are running on the PG (such as loading a block). If
you cannot ensure this state, disconnect all communication lines of the CPU.
Now, press the ejector and remove the MMC.
The module slot has an ejector device to enable you to remove the micro memory card
(see CPU 31xC and CPU 31x Manual, Technical Data
Operator Control and Display
Elements
).
Use a small screwdriver or ball-point pen to remove the MMC.
3. Insert the ("new") MMC into the MMC slot with the beveled edge of the MMC pointing
towards the ejector.
4. Gently insert the MMC into the CPU until the MMC clicks into place.
5. Reset CPU memory
(see Resetting CPU memory by means of mode selector switch)
CPU
Inserting and removing an MMC when CPU power is switched off
If you replace MMCs while the power is switched off, the CPUs
• will recognize a physically identical MMC with changed content
• a new MMC with the same content as the old MMC
It automatically performs a CPU memory reset after POWER ON.
Reference
• Properties of the Micro Memory Card (MMC) , CPU 31xC and CPU 31x Manual, Technical
data
•
Technical Data of the Micro Memory Card (MMC) , CPU 31xC and CPU 31x Manual,
Technical data

Siemens Simatic S7-300 CPU 31xC Series Specifications

General

Series	S7-300 CPU 31xC
Power Supply	24 V DC
Communication Interfaces	MPI, PROFIBUS DP
Programming Languages	LAD, STL, FBD, SCL
Operating Temperature	0°C to +60°C
Memory	48 KB - 512 KB
Dimensions	40 x 125 x 130 mm (varies by model)