Vega KFD0 Series, Product Information

Page: 7 / 16

4
C onnecting to power supply
4
.
1
P reparing the connection
N ote safety instructions
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 VEGA overvoltage arresters B 61 - 300
( external energy ) and B 62 - 36 G ( sensor supply ).
T ake note of safety instructions for E x applications
I n hazardous areas you should take note of the appro -
priate regulations
,
conformity and type approval certi fi
-
cates of the sensors and power supply units .
S
elect power supply
T he voltage supply for the E x separator VEGATRENN 149 AE x
must be in the rangeof 20 … 250 V AC , 50 / 60 H z or 20 … 250 V DC .
S electing connection cable
F
or power supply of
VEGATRENN 149 AE
x
,
an approved instal
-
lation cable with PE conductor is necessary .
T he sensor or the signal conditioning instrument are connected
with standard two - wire cable to the separator . I f strong electro -
magnetic interference is expected , screened cable should be
used .
C able screening and grounding
I f screened cable is used , connect the cable screen on both ends
to ground potential . I n the sensor , the screen must be connected
directly to the internal ground terminal . T he ground terminal on the
outside of the housing must be connected to the potential equal -
isation .
I f potential equalisation currents are expected , the screen con -
nection on the separator or signal processing instrument must be
made via a ceramic capacitor
( e . g . 1 n F , 1500 V ). T he low fre -
quency potential equalisation currents are thus suppressed , but
the protective e ff ect against high frequency interference signals
remains .
S elect connection cable for E x applications
T ake note of the corresponding installation regulations
for E x applications . I n particular , make sure that no po -
tential equalisation currents fl ow over the cable screen .
I n case of grounding on both sides this can be achieved
by the use of a capacitor or a separate potential equal
-
isation .
4 . 2 W iring plan
E x separator VEGATRENN
149
AE x
0+H
0+
0- L/+ N/-
0+H 0+ 0- L/+ N/-
I+ I-
1
2
3
4
F ig .
7
: T erminal assignment VEGATRENN
149
AE x
1
S ensor circuit
2 P rocessing circuit
3
P
ower supply
4 HART communication sockets
C
onnecting to power supply
S
eparating and protective instruments
– S
eparating and protective instruments
7
31996
-
EN
-
071204