Sysmac CPM1A-20CAR-A, Руководство по эксплуатации

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Glossary
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FA
Factory automation.
factory computer
A general-purpose computer, usually quite similar to a business computer, that
is used in automated factory control.
FAL error
An error generated from the user program by execution of an FAL(06) instruc-
tion.
FALS error
An error generated from the user program by execution of an FALS(07) instruc-
tion or an error generated by the system.
fatal error
An error that stops PLC operation and requires correction before operation can
continue.
FCS
See frame checksum .
flag
A dedicated bit in memory that is set by the system to indicate some type of oper-
ating status. Some flags, such as the carry flag, can also be set by the operator
or via the program.
flicker bit
A bit that is programmed to turn ON and OFF at a specific frequency.
floating-point decimal
A decimal number expressed as a number (the mantissa) multiplied by a power
of 10, e.g., 0.538 x 10
--5
.
force reset
The process of forcibly turning OFF a bit via a programming device. Bits are usu-
ally turned OFF as a result of program execution.
force set
The process of forcibly turning ON a bit via a programming device. Bits are usu-
ally turned ON as a result of program execution.
forced status
The status of bits that have been force reset or force set.
frame checksum
The results of exclusive ORing all data within a specified calculation range. The
frame checksum can be calculated on both the sending and receiving end of a
data transfer to confirm that data was transmitted correctly.
function code
A two-digit number used to input an instruction into the PLC.
hardware error
An error originating in the hardware structure (electronic components) of the
PLC, as opposed to a software error, which originates in software (i.e., pro-
grams).
header code
A code in an instruction that specifies what the instruction is to do.
hexadecimal
A number system where all numbers are expressed to the base 16. In a PLC all
data is ultimately stored in binary form, however, displays and inputs on Pro-
gramming Devices are often expressed in hexadecimal to simplify operation.
Each group of four binary bits is numerically equivalent to one hexadecimal digit.
host computer
A computer that is used to transfer data to or receive data from a PLC in a Host
Link system. The host computer is used for data management and overall sys-
tem control. Host computers are generally small personal or business comput-
ers.
host interface
An interface that allows communications with a host computer.
host link An interface connecting a PLC to a host computer to enable monitoring or pro-
gram control from the host computer.
HR area
A memory area that preserves bit status during power interrupts and used as
work bits in programming.
I/O bit
A bit in memory used to hold I/O status. Input bits reflect the status of input termi-
nals; output bits hold the status for output terminals.