Vega VEGASON 63, Руководство по эксплуатации

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5
C onnecting to power supply
5
.
1
P reparing 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
T ip :
W
e recommend using
VEGA
overvoltage arresters Ü
S - F - LB - I
and Ü
SB
62
-
36
G . X .
I
n hazardous areas you should take note of the appropriate
regulations
,
conformity and type approval certi
fi
cates of the
sensors and power supply units
.
P
ower supply and current signal are carried on the same two
-
wire cable
. T
he voltage supply range can di
ff
er depending on
the instrument version
.
T
he data for power supply are stated in chapter
" T echnical
data "
in the
"
S
upplement "
.
P
rovide a reliable separation between the supply circuit and
the mains circuits according to
DIN VDE
0106
part
101
. T
he
VEGA
power supply units
VEGATRENN
149
A E
x
, VEGAS -
TAB
690
as well as all
VEGAMET
s meet this requirement
.
B
ear in mind the following factors regarding supply voltage
:
l
O
utput voltage of the power supply unit can be lower under
nominal load
(
with a sensor current of
20
.
5
m
A
or
22
m
A
in
case of fault message
)
l
I
n
fl
uence of additional instruments in the circuit
(
see load
values in chapter
" T echnical data " ).
VEGASON
63
is connected with standard two
-
wire cable
without screen
. A
n outer cable diameter of
5
…
9
mm ensures
the seal e
ff
ect of the cable gland
. I
f electromagnetic
interference is expected which is above the test values of
EN
61326
for industrial areas
,
screened cable should be used
.
F
or
HART
multidrop operation we recommend as standard
practice the use of screened cable
.
O
n
VEGASON
63
with cable gland
½
NPT
and plastic housing
,
a metal
½"
threaded insert is moulded in the plastic housing
.
N ote safety instructions
T ake note of safety
instructions for E x
applications
S elect power supply
S electing connection cable
C able gland ½ NPT
VEGASON
63
-
4
...
20
m
A / HART
21
C
onnecting to power supply
28777
-
EN
-
070507