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Hazardous area installations
D.3 EU equivalency
SITRANS Probe LR with mA/HART
Operating Instructions, 05/2019, A5E32337711-AC
99
①
Zone 0,1 or 2
Load 4-20 mA
②
Certified barrier
③
PLC (active)
④
HART handheld communicator
D.3
EU equivalency
Any zener diode safety barrier, certified by an EU approved certification body to [ EEx ia ]
IIC, its output voltage (U
o
) not exceeding 30 V and its output current (I
o
) limited by load
resistance (R
o
); such that I
o
= U
o
/ R
o
, does not exceed 120 mA.
Note
•
The electrical circuit in the hazardous area must be capable of withstanding an AC test
voltage of 500 V rms to earth or frame of the apparatus for one minute.
•
The installation must comply with national requirements.
•
The safe area is unspecified except that it must not be supplied from nor contain, under
normal or abnormal conditions, a source of potential with respect to earth in excess of
250 V rms or 250 V DC.