4
2.3 Fieldbus connection
The BA418CF-F Indicator is powered and
communicates via the fieldbus, which is connected
to terminals 1 and 2. These are non-polarised,
comply with the Fieldbus Intrinsically Safe Concept
(FISCO) defined in EN 60079 Part 27 and have
separate entity parameters shown below:
FISCO Entity
Ui
=
17.5V dc
22.0V dc
Ii
=
380mA dc
250mA dc
Pi
=
5.32W
1.2W
The maximum equivalent capacitance and
inductance at terminals 1 & 2 is:
Ci
= 0
Li
= 8µH
2.4 Certification Label Information
The certification information label is fitted to the top
outer surface of the enclosure. It shows details of
the ATEX certification and a statement that the
instrument is a FISCO Field Device, plus BEKA
associates name and location. IECEx approval
information is also included. The label may also
contain non-European certification information.
The instrument serial number and year of
manufacture are shown on the rear panel.
The instrument serial number is shown on the rear
of the instrument adjacent to the terminals.
3. SYSTEM DESIGN FOR HAZARDOUS
AREAS
3.1 FISCO Systems
The BA418CF-F may be connected to any ATEX
certified FISCO compliant fieldbus segment,
providing the segment can supply the additional
13mA required to power the instrument.
Fig 1 shows a typical fieldbus segment. To comply
with FISCO requirements, the power supply,
terminators, field devices and the interconnecting
cables must conform with EN 60079 part 27.
Fig 1 FISCO fieldbus system
3.2
Non-FISCO Systems
For non-FISCO applications the BA418CF-F
Fieldbus Indicator has a higher voltage entity
intrinsic safety input parameter allowing connection
to a wide range of fieldbus segments.
The BA418CF-F Fieldbus Indicator may be
connected to any intrinsically safe segment
providing:
The device powering the fieldbus segment is
ATEX certified and has output parameters
equal to or less than:
Uo
=
22V dc
Io
=
250mA dc
Po
=
1.2W
The segment can provide an additional
13mA to power the Fieldbus Indicator.
Note:
The equivalent capacitance Ci of the
BA418CF-F Fieldbus Indicator is zero and
the equivalent inductance is insignificant.
Therefore these BA414DF parameters do
not need to be considered.
