5 connecting to power supply, 1 preparing the connection, 5connecting to power supply – VEGA VEGABAR 17 User Manual
Page 12
5
Connecting to power supply
5
.1 Preparing the connection
A
lways keep in mind the following safety instructions:
l
C
onnect only in the complete absence of line voltage
l
I
f overvoltage surges are expected, overvoltage arresters should
be installed
Tip:
W
e recommend VEGA overvoltage arrester ÜSB 62-36G.X.
I
n hazardous areas you must take note of the respective regulations,
conformity and type approval certificates of the sensors and power
supply units.
T
he supply voltage and the current signal are carried on the same two-
wire connection cable.
P
rovide a reliable separation between the supply circuit and the mains
circuits according to DIN VDE 0106 part 101.
VEGA
power supply units VEGATRENN 149AEx, VEGASTAB 690,
VEGADIS
371
as well as all VEGAMETs meet this requirement. When
using one of these instruments, protection class III is ensured for
VEGABAR
17.
K
eep in mind the following additional factors that influence the
operating voltage:
l
O
utput 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
I
nfluence of additional instruments in the circuit (see load values in
chapter "Technical data")
T
he 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.
U
se 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.
F
or the version with round plug connector M12 x 1, a suitable, ready-
made connection cable (article no. ASL.1S.) in 5 m, 10 m or 25 m
lengths is available from the line of VEGA accessories.
Note safety instructions
Take note of sa-
fety instructions
for Ex applica-
tions
Select power supply
Select connection cable
12
VEGABAR
17
5 C
onnecting to power supply
27636
-EN
-120531