Connecting To Power Supply; Preparing The Connection - T&D VEGAWELL 52 Operating Instructions Manual

Safety instructions
Take note of sa-
fety instructions
for Ex applica-
tions
Select power supply
Select connection cable
VEGAWELL 52 • 4 ... 20 mA

5 Connecting to power supply

5.1 Preparing the connection

Generally connect the instrument only in the complete absence of line
voltage.
The instrument is equipped with an integrated overvoltage protection.
For additional protection of the signal circuit, we recommend further
external overvoltage arresters:
Type B63-48 (use with VEGAWELL 52 with plastic housing) or
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Type ÜSB 62-36G.X (use in a separate housing)
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In hazardous areas you must take note of the respective regulations,
conformity and type approval certificates of the sensors and power
supply units.
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.
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
VEGAWELL 52.
Keep in mind the following additional factors that influence the
operating voltage:
Output voltage of the power supply unit can be lower under
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nominal load (with a sensor current of 20.5 mA or 22 mA in case of
fault message)
Influence of additional instruments in the circuit (see load values in
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chapter "Technical data")
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.
5 Connecting to power supply
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