KROHNE IFC 110 Converter - Manual (Page 14)

Sect. 1.3.6 Part A System installation and start-up
14 IFC 110 F 05/2003
1.3.6 EEx-Connection diagrams for power supply and flow sensors
PLEASE NOTE!
• The figures in brackets indicate the stranded drain wires for the shields (see cross-sectional
drawing of signal cable in Section 1.3.1).
• The connections for the intrinsically safe electrode circuit including the shield terminals
are safety-separated up to a peak value of 375 V from the terminals for thepower supply,
for the inputs/outputs and for the field circuit. They are galvanically isolated from the housing
(PE/PA).
• For connection of the intrinsically safe electrode circuit including shield terminals to the
primary head, please refer to Item 12 in EN 60079-14.
The non-intrinsically safe field circuit to be connected to the primary head in keeping with the
requirements of Item 9 in EN 60079-14 .
• The non-intrinsically safe input and output circuits may only be routed into the hazardous
area in compliance with appropriate measures as specified in EN 60079-14.
• Supply power (terminals 11,12)
In conformity with current regulations for electrical installations, an isolating facility is required
to be provided for the signal converter. The housing of the IFC 110 F – EEx signal converter
must be incorporated in the equipotential bonding system (via external PA connection).
Note!
A PE safety conductor is not connected if a functional extra-low voltage with safety
separation (PELV) is used. Grounding is then carried out by way of the equipotential
bonding conductor.
• Electrode circuit (terminals 1, 20, 2, 3, 30 and shield terminal S)
In conformity with the requirements for separation of intrinsically safe circuits, Category ib to
EN 50 020, the cable for the intrinsically safe electrode circuit must, up to the terminals, be
separated from all non-intrinsically safe circuits.
Terminals 20 and 30 are optionally provided for connecting cables with single shielding. The
terminal for the outer shield (S) is capacitance grounded in the signal converter. The outer
overall shield to be connected by the shortest possible wire to the shield terminal. Shields to
be carefully insulated from ground and from each other.
• Field circuit FSV (terminals 7, 8)
The field circuit is all-pole protected on the FSV circuit board with an internal fusible link
160mA / 250V.
• Input/output circuits
The connection is made to functional extra-low voltage circuits with safety separation (PELV).
The I/O functions and technical data are described in the Standard Installation and Operating
Instructions.
IMPORTANT!
For EEx versions, also pay regard to all directions included in Sect. 6.1 and 13.
Only the EEx flow sensor may be installed in the hazardous area. The EEx
certified signal converter must be installed outside the hazardous area!
* Do not remove the internal connection (cable) inside the terminal compartment of the signal
converter (yellow/green wire) between the U-clamp terminal and terminal 10 (protective
conductor for protection class I instruments).