Harmony eXLhoist, Руководство пользователя

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Glossary
EIO0000001505 12/2014
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M
MAC address
(Media Access Control address) A unique 48-bit number associated with a specific piece of
hardware. The MAC address is programmed into each network card or device when it is
manufactured.
MTTF
(Mean TIme To Failure)
N
NC
(Normally Closed) A contact pair that closes when the actuator is de-energized (no power is
applied) and opens when the actuator is energized (power is applied).
NEMA
(National Electrical Manufacturers Association) The standard for the performance of various
classes of electrical enclosures. The NEMA standards cover corrosion resistance, ability to help
protect from rain, submersion, and so on. For IEC member countries, the IEC 60529 standard
classifies the ingress protection rating for enclosures.
NO
(Normally Open) A contact pair that opens when the actuator is de-energized (no power is applied)
and closes when the actuator is energized (power is applied).
P
PC
(Personal Computer)
PELV
(Protective Extra Low Voltage)
PFD
(Probability of Failure on Demand)
PL
(Performance Level)
PST
(Process Safety Time)