Eaton EASY222-DN, Руководство пользователя

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Glossary
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Bit Abbreviation for the English “binary digit“. Represents the
smallest information unit of a binary system. Its significance
can be 1 or 0 (Yes/No decision).
Lightning protection Represents all measures for preventing system damage due
to overvoltage caused by lightning strike.
Bus Bus system for data exchange, for example between the
CPU, memory and I/O. A bus can consist of several parallel
segments, e.g the data bus, address bus, control bus and
power supply bus.
Bus line Smallest unit connected to the bus. Consists of the PLC, a
module and a bus interface for the module.
Bus system All units as a whole which communicate across a bus.
Bus cycle time Time interval in which a master provides services to all
slaves or nodes of a bus system, i.e. writes data to their
outputs and reads inputs.
Byte A sequence of 8 bits
Code Data transfer format
COS I/O connection COS (Change Of State) I/O connections are used to establish
event-controlled connections. This means that the Devi-
ceNet devices generate messages from themselves as soon
as a status change is present.
2 byte diagnostics data of the easy control relay
Coupling module status
CPU Abbreviation for “Central Processing Unit”. Central unit for
data processing, which represents the core element of a
computer.
Cyclic I/O connection Message triggering is timer-controlled when operating with
a cyclic I/O connection.
Device Heartbeat Message A DeviceNet unit can use the Device Heartbeat Message
function to broadcast its native status at set time intervals.
These messages are configured in the Identity Object.
Device Shut Down Message A device shutting down due to internal errors or states can
log off at the PLC by means of the Device Shut Down
Message.