Siemens Simatic S7-1500R System Manual page 314

Distributed I/O system
System with I/O modules that are configured on a distributed basis, at a large distance from
the CPU controlling them.
DP
Distributed I/O
Equipotential bonding
Electrical connection (equipotential bonding conductor) that brings the conductive parts of
electrical equipment and other conductive parts to the same or approximately the same
potential. This prevents disruptive or dangerous voltages arising between these parts.
Firmware of the CPU
In SIMATIC, a distinction is made between the firmware of the CPU and user programs.
The firmware is a software embedded in electronic devices. The firmware is permanently
connected to the hardware in functional terms. It is usually saved in a flash memory, such as
EPROM, EEPROM or ROM, and cannot be replaced by the user or only with special tools or
functions.
User program: You will find further information in the glossary entry "User program".
Firmware update
You update the module firmware with a firmware update. A firmware update is, for example,
run for new functions of a CPU or an interface module.
Function
A function (FC) is a code block with no static data. A function allows you to pass parameters
in the user program. Functions are thus suited for programming frequently recurring complex
functions, such as calculations.
Function block
A function block (FB) is a code block with static data. An FB allows you to pass parameters
in the user program. Function blocks are thus suited for programming frequently recurring
complex functions, such as closed-loop controls or operating mode selection.
Functional ground
Functional ground is a low-impedance current path between electric circuits and ground. It is
not intended as a protective measure but rather, for example, for improvement of
interference immunity.
S7-1500R/H redundant system
System Manual, 10/2018, A5E41814787-AA
Glossary
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