Glossary - Eaton ESR5-NO-31-24VDC Manual

7 Glossary

Abbreviation Description
AC-15, DC-13 Standardized utilization categories and load cases from standard IEC 60947-5-1 that are
used to test switching elements, i.e., switching on and off with defined voltages, currents,
and loads (electromagnetic loads in particular in this case).
AOPD Active Opto-electronic Protective Device
Device with a sensor function that is implemented with optoelectronic transmission and
reception elements that detect when an opaque object in the defined area of protection (or
in the way of the light beam axis in the case of light barriers) is blocking the beams gener-
ated by the device.
AOS is used as an abbreviation synonymous with AOPD in DIN EN 692 ("Machine tools -
Mechanical presses - Safety"), DIN EN 693 ("Machine tools - Safety - Hydraulic presses"),
and EN 12622 ("Safety of machine tools - Hydraulic press brakes").
AOPDDR Active Opto-electronic Protective Device responsive to Diffuse Reflection
Device with a sensor function that is implemented with optoelectronic transmission and
reception elements that detect when an object in the area of protection defined with two
dimensions diffusely reflects the beam generated by the device.
ESPE Electro-sensitive protective equipment
CCF Common Cause Failure
Common cause failure
DC Diagnostic Coverage
Diagnostic coverage
ESR Electronic safety relay
DF Duty factor
PL Performance Level
Classification of safety functions used to meet a safety requirement.
HFT Hardware Fault Tolerance
Cat. / category Classification of resistance to errors as defined in EN ISO 13849-1
Mission Time T Lifetime
M
MTTF / MTTF Mean Time To Failure
d
Mean time to failure / mean time to dangerous failure
NC Normally Closed contact, break contact
An NC breaks a circuit when it is energized.
Normally-Open contact
NO
An NO closes when it is energized.
PFD Probability Failure on Demand (Low-Demand)
Probability of failure relative to the number of requests
PFH Probability of a Dangerous Failure per Hour
d
Probability of dangerous Failures per Hour
SIL Safety Integrity Level
Safety integrity level
SRCF Safety-Related Control Function
Safety-related control function
SRECS Safety-Related Electrical Control System
Safety related electrical, electronic, programmable electronic control system
SRP Safety-Related Part
Safety-related part
SRP/CS Safety-Related Parts of Control System
Safety-related part of a control system
ESR5-NO-31-24VDC 11/23 MN049018EN Eaton.com
7 Glossary
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