VEGA VEGAPULS 51K…54K 4 … 20 mA; HART compact sensor - Manual (Page 27)

VEGAPULS 51K … 54K 27
21750-EN-031222
Ex protection
If an instrument is used in hazardous areas,
the respective regulations, conformity certifi-
cates and type approvals for systems in Ex
areas must be noted (e.g. DIN 0165).
Intrinsically safe circuits with more than one
active instrument (instrument delivering elec-
trical energy) are not allowed. Special instal-
lation regulations (DIN 0165) must be noted.
Note!
Due to the possibility of potential transfer,
earthing on both ends is prohibited in Ex
applications.
Ground terminals
On VEGAPULS 51 and 52 sensors with 1½“
plastic thread, the ground terminal is galvani-
cally isolated. The sensors have a protective
insulation.
On VEGAPULS 53 and 54 sensors as well as
51 and 52 sensors with metal thread, the
ground terminal is galvanically connected to
the flange or thread.
Electrical connection
4.2 Connecting the sensor
After mounting the sensor at the measure-
ment location according to the instructions in
chapter „3 Mounting and installation“, loosen
the closing screw on top of the sensor. The
sensor lid with the optional indicating display
can then be opened. Unscrew the sleeve nut
and slip it over the connection cable (after
removing about 10 cm of cable mantle). The
sleeve nut of the cable entry has a self-lock-
ing ratchet that prevents it from opening on
its own.
Now insert the cable through the cable entry
into the sensor. Screw the sleeve nut back
onto the cable entry and clamp the stripped
wires of the cable into the proper terminal
positions.
The terminals hold the wire without a screw.
Press the white opening tabs with a small
screwdriver and insert the copper core of the
connection cable into the terminal opening.
Check the hold of the individual wires in the
terminals by lightly pulling on them.