User Manual

5 Connecting to power supply
5.1 Preparing the connection
Always keep in mind the following safety instructions:
l Connect only in the complete absence of line voltage
l If overvoltages are expected, install overvoltage arresters
Power supply and current signal are carried on the same two-wire
cable. The voltage supply range can differ depending on the
instrument version.
The data for power supply are specified in chapter "Technical data".
Provide a reliable separation between the supply circuit and the mains
circuits according to DIN VDE 0106 part 101.
Keep in mind the following additional influences on the operating
voltage:
l Output voltage of the power supply unit can be lower under
nominal load (with a sensor current of 20.5 mA or 22 mA in case of
fault message)
l Influence of additional instruments in the circuit (see load values in
chapter "Technical data")
The signal conditioning instruments VEGAMET and VEGASCAN have
digital sensor recognition. When connecting VEGAPULS 62, an up-to-
date software version of the signal conditioning instrument is required
for the signal conditioning instrument. For a software update go to
"
Software" under "www.vega.com/downloads".
The instrument is connected with standard two-wire cable without
screen. If electromagnetic interference is expected which is above the
test values of EN 61326 for industrial areas, screened cable should be
used.
Use cable with round cross-section. A cable outer diameter of 5 … 9 mm
(0.2 … 0.35 in) ensures the seal effect of the cable gland. If you are
using cable with a different diameter or cross-section, exchange the
seal or use a suitable cable gland.
We generally recommend the use of screened cable for HART
multidrop mode.
With plastic housing, the NPT cable gland or the Conduit steel tube
must be screwed without grease into the threaded insert.
Max. torque for all housings see chapter "Technical data"
Safety instructions
Voltage supply
Connection to signal
conditioning instru-
ments
Connection cable
Cable gland ½ NPT
VEGAPULS 62 • 4 … 20 mA/HART two-wire 25
5 Connecting to power supply
36503-EN-100607