ABB CL Series Applications Manual page 74

1SVC 440 795 M0100
CL operation
Circuit diagram
The circuit diagram is that part of the program where the
contacts are connected together. In RUN mode a coil is
switched on and off in accordance with the current flow and
the coil function specified.
Function relay
Function relays are program elements with special functions.
Example: timing relays, time switches, counters. Function
relays are elements provided with or without contacts and
coils as required. In RUN mode the function relays are
processed according to the circuit diagram and the results
are updated accordingly.
Examples:
Timing relay = function relay with contacts and coils
Time switch = function relay with contacts
Relays
Relays are switching devices which are electronically
simulated in the logic relay. They actuate their contacts
according to their designated function. A relay consists of at
least a coil and a contact.
Contacts
You modify the current flow with the contacts in the CL
circuit diagram. Contacts such as n/o contacts are set to 1
when they are closed and 0 when they are opened.
Every n/o or n/c contact in the CL circuit diagram can be
defined as either a n/o contact or a n/c contact.
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