User guide

ELECTRICAL CONNECTIONS 4
27
OPTISONIC 7300 / 8300
www.krohne.com05/2012 - 7312262200 - AD EX OPTISONIC 7300/8300 R02
4.3 "Ex i" I/O connections
The following intrinsically safe I/O connections are available:
The I/O circuits titled “Ex i IO” , "Ex i Option" and “Ex i Option 2” are always provided with type of
protection Intrinsic Safety (Ex ia). The I/O-circuits “Fieldbus I/O Profibus-PA” as well as “Fieldbus
I/O Foundation Fieldbus” can be provided with type of protection Intrinsic Safety.
Up to a maximum of 4 intrinsically safe (Ex ia) in-/outputs are possible. All intrinsically safe
circuits are galvanically isolated from earth and each other. To avoid summation of voltages and
current, the wiring of these “Ex ia”-circuits must be sufficiently separated, e.g. in accordance
with the requirements of standard EN 60079-14, clause 12.2.
The “Ex ia” in-/outputs may only be connected to other “Ex ia” or “Ex ib” approved devices (e.g.
intrinsically safe isolation amplifiers), even if such devices are installed in a non-hazardous
location!
Connection to non-“Ex i” devices cancels the “Ex ia” properties of the flowmeter.
Terminals L and N (or L+ and L-) for connection of the mains supply are not available with type of
protection “intrinsic safety”. To achieve the necessary separation distances according to EN
60079-11 between the non-”Ex i” and “Ex i” circuits, the mains terminals are provided with a
semi-circular protection cover with a “snap-in” lock. This cover MUST be closed before
establishing the power supply to the converter.
I/O PCB I/O functions
Ex i IO Current Output, passive + HART
communication
Pulse / Status Output, passive
Ex ia IIC or Ex ib IIC
U
i
= 30 V, I
i
= 100 mA, P
i
= 1.0 W
C
i
= 10 nF, L
i
= negligibly low
Current Output, active + HART
communication
Ex ia IIC or Ex ib IIC
U
o
= 21 V, I
o
= 90 mA, P
o
= 0.5 W
Lineair characteristics
C
o
= 90 nF, L
o
= 2.0 mH
C
o
= 110 nF, L
o
= 0.5 mH
Ex i Option Current Output, passive
Pulse / Status Output / Control
Input, passive
Ex ia IIC or Ex ib IIC
U
i
= 30 V, I
i
= 100 mA, P
i
= 1.0 W
C
i
= 10 nF, L
i
= negligibly low
Current Output, active Ex ia IIC or Ex ib IIC
U
o
= 21 V, I
o
= 90 mA, P
o
= 0.5 W
Lineair characteristics
C
o
= 90 nF, L
o
= 2.0 mH
C
o
= 110 nF, L
o
= 0.5 mH
Ex i Option 2 Current Input, passive
Pulse / Status Output / Control
Input, passive
Ex ia IIC or Ex ib IIC
U
i
= 30 V, I
i
= 100 mA, P
i
= 1.0 W
C
i
= 10 nF, L
i
= negligibly low
Current Input, active Ex ia IIC or Ex ib IIC
U
o
= 24.1 V, I
o
= 99 mA, P
o
= 0.6 W
Lineair characteristics
C
o
= 75 nF, L
o
= 0.5 mH
Fieldbus I/O Profibus-PA
Foundation Fieldbus, passive
Ex ia IIC or Ex ib IIC / IIB
U
i
= 24 V, I
i
= 380 mA, P
i
= 5.32 W
C
i
= 5 nF, L
i
= 10 µH
Suitable for connection to an
intrinsically safe fieldbus in
accordance with the FISCO-
model