IFM Electronic Ecomat Mobile Series, System Manual

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ifm System Manual ecomat mobile SmartController (CR2500) V05
Glossary of Terms
The MTTF
d
is the expectation of the mean time
to dangerous failure.
Designation Range
low 3 years < MTTF
d
< 10 years
medium 10 years < MTTF
d
< 30 years
high 30 years < MTTF
d
< 100 years
Table: Mean time of each channel to the dangerous failure
MTTF
d
Link
A link is a cross-reference to another part in
the document or to an external document.
M
MAC-ID
MAC = M anufacturer‘s A ddress C ode =
manufacturer's serial number
→
ID = Id entifier
Every network card has a MAC address, a
clearly defined worldwide unique numerical
code, more or less a kind of serial number.
Such a MAC address is a sequence of
6 hexadecimal numbers, e.g. "00-0C-6E-D0-
02-3F".
Master
Handles the complete organisation on the bus.
The master decides on the bus access time
and polls the
→
slaves cyclically.
Mission time TM
Mission time T
M
is the period of time covering
the intended use of an SRP/CS.
Misuse
The use of a product in a way not intended by
the designer.
The manufacturer of the product has to warn
against readily predictable misuse in his user
information.
Monitoring
Safety function which ensures that a protective
measure is initiated:
•
if the ability of a component or an element
to perform its function is diminished.
•
if the process conditions are changed in
such a way that the resulting risk
increases.
MTBF
M ean T ime B etween F ailures (MTBF)
Is the expected value of the operating time
between two consecutive failures of items that
are maintained.
NOTE: For items that are NOT maintained the
mean life
→
MTTF is the expected value (mean
value) of the distribution of lives.
MTTF
M ean T ime T o F ailure (MTTF) or: mean life.
MTTFd
M ean T ime T o F ailure (MTTF) or: mean life.
The MTTF
d
is the expectation of the mean time
to dangerous failure.
Designation Range
low 3 years < MTTF
d
< 10 years
medium 10 years < MTTF
d
< 30 years
high 30 years < MTTF
d
< 100 years
Table: Mean time of each channel to the dangerous failure
MTTF
d
Muting
Muting is the temporary automatic suspension
of a safety function(s) by the SRP/CS.
Example: The safety light curtain is bridged, if
the closing tools have reached a finger-proof
distance to each other. The operator can now
approach the machine without any danger and
guide the workpiece.