IFM Ecomat 300 AC1355, Supplementary Device Manual

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Terms, abbreviations
15-5
Remanent Remanent data is protected against data loss in case of power failure.
The operating system for example automatically copies the remanent data to a
flash memory as soon as the voltage supply falls below a critical value. If the
voltage supply is available again, the
→
operating system loads the remanent
data back to the RAM memory.
The data in the RAM memory of a controller, however, is volatile and normally
lost in case of power failure.
RTS RTS =
R
un
T
ime
S
ystem
Run time systems are basic versions of applications. These minimum versions
are supplied with certain products to meet the prerequisites for the execution
of the actual product or to be able to look at or use results generated by this
product on other processors: making available all routines required to execute
a program in a programming language, e.g. interactions with the
→
operating
system, memory requirements, error routines, inputs and outputs.
SELV SELV =
S
afety
E
xtra
L
ow
V
oltage
Active parts integrated in SELV circuits must not be connected to ground or
protective conductors of other circuits. They must be safely separated from
active parts with higher voltage.
SELV circuit = secondary circuit (output voltage) which is rated and protected
so that its voltages do not exceed a safe value in case of correct operation (of
the power supply) or in case of a single fault (of the power supply).
SELV circuits are separated from the input voltage (mains voltage) by double
or enhanced insulation. The voltage value must not exceed 60 V DC (or 42.4 V
AC).
Single slave
→ Slave whose address number may only occur once on the → master.
Slave
Passive participant at the bus, only replies on request of the → master. Slaves
have a clearly defined and unique
→
address in the bus. The following
distinction is made:
single slaves whose address numbers may only occur once on the
→
master
and
A/B slaves with an A or B being appended to their address number which may
therefore be present in the
→ master twice.
Target The target indicates the target system where the PLC program is to run. The
target contains the files (drivers) required for programming and parameter
setting.
Unit ID →
DPV1
Watchdog In general the term watchdog is used for a component of a system which
watches the function of other components. If a possible malfunction is
detected, this is either signalled or suitable program branchings are activated.
The signal or the branchings serve as triggers for other co-operating system
components which are to solve the problem.
Cycle time This is the time for one cycle. The following happens:
PLC cycle: the PLC program performs one complete run.
AS-i cycle: all AS-i slaves are updated (5...10 ms).