Eaton ZB12/XTOB BC1 Series, Manual

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03/15 MN03407004Z-DE/EN
About This Manual
This manual applies to the ZB12/XTOB…BC1 and
ZB32/XTOB…CC1 overload relays.
It describes the overload monitoring system for the
protection of motors operating in potentially explosive
atmospheres Ex e areas.
Target group This manual is aimed at specialist personnel who are
responsible for the installation, commissioning and
maintenance of overload relays.
Abbreviations and
symbols Symbols used in this manual have the following meanings:
X
indicates actions to be taken.
Ex e Type of protection “Increased Safety”
FIT F ailure I n Time
(number of dangerous failures in 10
9
hours)
HFT H ardware- F ault- T olerance
HM Highest possible setting current
MTTF
d
M ean T ime T o D angerous F ailure
NM Lowest possible setting current
PL P erformance L evel
PTB P hysikalisch- T echnische B undesanstalt
(German Federal Testing Laboratory:
Accredited certification authority for devices
operated in Ex e areas)
SIL S afety I ntegrity L evel
h
Draws your attention to interesting tips and
supplementary information