4
ELECTRICAL CONNECTIONS
36
OPTIFLUX
www.krohne.com
07/2010 - 7309482600 - AD EX IFC 300 R06 en
Up to a maximum of 4 intrinsically safe (Ex ia) in-/outputs are possible. All intrinsically safe
circuits are galvanically insulated with respect to 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
”
signal 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.
INFORMATION!
For converters with an
“
Ex e
”
terminal compartment, the compartment can be opened in an
energized state for short periods of time, to access the intrinsically safe terminals for possible
checks. However, the semi-circular insulation cover over the non-intrinsically safe mains supply
terminals L and N (or L+ and L-) MUST be kept closed.
INFORMATION!
More detailed information about the connections can be found in the handbook of the converter.