VEGA D91 Profibus PA - Manual (Page 15)

Pressure transmitter D91 (Profibus PA) 15
Electrical connection
3 Electrical connection
3.1 Connection instructions
The electronics in pressure transmitter D91
requires a supply voltage of 9 … 32 V DC.
The supply voltage and the digital output
signal are led via the same two-wire cable to
the terminals. The external energy is pro-
vided via a segment coupler.
Note the following instructions for electrical
connection:
- Connection must be made according to the
country-specific installation standards (e.g.
in Germany acc. to the VDE regulations).
- The electrical connection must have a pro-
tective measure against polarity reversal.
- The connection of field instruments is gen-
erally made via T-adapters on stubs..
- Screened cable is recommended for con-
nection (cable types, see chapter "1.3
Technical data"). The shielding must be
grounded on both ends (on the T-adapter
and on the connection housing of D91).
- For use in Ex areas, the installation regula-
tions must be observed.
Safety information for Ex applications
As a rule, do all connecting work in the com-
plete absence of line voltage. Always switch
off the power supply before you carry out
connecting work on the sensors. Protect
yourself and the instruments.
Qualified personnel
Instruments used in Ex areas must be in-
stalled only by qualified personnel. The quali-
fied personnel must observe and understand
the mounting regulations and the supplied
type approval and conformity certificates.
If an instrument is used in hazardous areas,
the respective regulations, conformity certifi-
cates and type approvals of the sensors,
separators or safety barriers must be noted
(e.g. DIN VDE 0165).
Sensors used in Ex areas must be con-
nected only to intrinsically safe circuits. The
permissible electrical values are stated in the
conformity certificate or the type approval
certificate.
Intrinsically safe circuits with more than one
active instrument (instrument delivering elec-
trical energy) are not allowed. Please note the
special installation regulations (DIN VDE
0165).
Certain pressure transmitters are provided
with a warning label informing of measures to
be taken to avoid the danger of electrostatic
discharge. Note the content of the warning
label.