What is system memory in PLC?
System Memory: It’s part of the memory where it can store the addressing part of the PLC program like Inputs, Outputs, Timers, Counters, and Bit memory.
What is user memory in PLC?
In the PLC user memory of the PLC CPU, the PLC user program and the user data are stored together with the PLC basic program. The memory of the PLC CPU is segmented according to load memory, work memory and system memory.
What is load memory in Siemens PLC?
Load memory is a non-volatile storage memory for the user program, data, and configuration. Therefore, when a program is downloaded to the CPU, it will first stored in the load memory area. Load memory can be expanded using memory cards, it is generally called MMC(Micro Memory Card).
What is memory and explain Siemens memory types?
CPU memory in Siemens S7 consists of three sections: 1) Load Memory 2) Work Memory 3) System Memory Tips: 1- PII, PIQ, and I/Os load in System Memory and sometimes in Work Memory for new processors.
What is a retentive memory type?
Retentive memory is memory that is configured by the user to maintain values through a power cycle or a PROGRAM to RUN transition. Non-retentive memory is memory that is configured by the PLC user to clear data after a power cycle or a PROGRAM to RUN transition.
What type of memory is eeprom?
EEPROM (electrically erasable programmable read-only memory) is user-modifiable read-only memory (ROM) that can be erased and reprogrammed (written to) repeatedly through the application of higher than normal electrical voltage. Unlike EPROM chips, EEPROMs do not need to be removed from the computer to be modified.
What is load memory?
Load memory is non-volatile storage for the user program, data and configuration. When a project is downloaded to the CPU, it is first stored in the Load memory area. This area is located either in a memory card (if present) or in the CPU. This non-volatile memory area is maintained through a power loss.
What is work memory in Siemens PLC?
Work memory is volatile storage for some elements of the user project while executing the user program. The CPU copies some elements of the project from load memory into work memory. This volatile area is lost when power is removed, and is restored by the CPU when power is restored.