5. Programming on the device
5.3 Circuit diagram elements
5.3 Circuit diagram elements
A circuit diagram is a series of commands that the easyE4 device processes cyclically
in RUN operating mode.
Coils and contacts are interconnected in the circuit diagram. In RUN mode, a coil is
switched on or off depending on the power flow and coil function set.
5.3.1 Function blocks
Function blocks are program elements with special functions. Examples: Timing relays,
time switch, data block comparators. Function blocks are provided with or without con-
tacts and coils. How a safety or standard function block is added to the safety or stand-
ard circuit diagram and parameterized is described in
→ Section "Working with function blocks", page 154
In RUN mode the function blocks are processed according to the circuit diagram and
the results are updated accordingly.
Examples:
Timing relay = Function block with contacts and coils
Time switch = Function block with contacts
5.3.2 Relays
Relays are switching devices that are emulated in easyE4 device electronically, which
activate their contacts according to the assigned function. A relay consists of at least
one coil and contact.
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