Siemens Simatic CFU Commissioning Manual page 157

Equipotential bonding
Electrical connection (potential equalization conductor) that brings the bodies of electrical
equipment and other conductive bodies to the same or almost the same potential, in order to
prevent disruptive or dangerous voltages between these bodies.
Fiber-optic cable
Possibility for transferring data across large distances. A major advantage of fiber-optic cables
compared to electrical lines is that the data transfer cannot be influenced by electrical or
magnetic fields.
The optical interfaces are specified in the following standards:
● ISO/IEC 9314-3 (multimode)
● ISO/IEC 9314-4 (single-mode)
You can use both multimode fiber-optic cables and single-mode fiber-optic cables as fiber-
optic cables for PROFINET networks. Typical manufacturer variants are:
● GOF -
● POF -
Firmware update
Upgrade of firmware for devices or modules (interface modules, I/O modules etc.) to the newest
firmware version (update), for example after enhancement of functions.
Functional ground
Functional ground is a low-impedance current path between electric circuits and ground. It is
not designed as a safety measure but instead, for example, as a measure to improve
interference immunity.
GOF
GOF -
Ground
All interconnected, inactive parts of a piece of equipment that cannot accept any dangerous
contact voltage, even in the event of a fault.
Grounding
Grounding means connecting an electrically conductive part to a grounding electrode by
means of a grounding system.
SIMATIC CFU
Commissioning Manual, 07/2018, A5E39252870-AC
Glass Optical Fibers
Plastic Optical Fibers or POFs are fiber-optic cables made of plastic.
Glass Optical Fibers -> Fiber-optic cables
Glossary
157