Connections
General Requirements
4
Connections
N
ote on safety
A
lways observe the following safety instructions
:
C
onnect only in the complete absence of line voltage
If overvoltages are expected
,
overvoltage arresters should be installed
.
A safety certified power supply which provides double insulation between the
primary and output must be used for powering the unit. The power supply must be
limited power source with output rating 20-32VDC, 1A.
In hazardous areas you should take note of the appropriate regulations,
conformity and type of approval certificates of the sensors and power supply
units.
4.1
General Requirements
The power supply range can differ depending on the device version. See the
Technical
data, page 35
, for full details.
4.2
Power Supply
A safety certified power supply which provides double insulation between the primary
and output must be used for powering the unit. The power supply must be limited
power source with maximum output current 1A. The power supply voltage range
should be 20 V DC minimum and 32 V DC maximum
4…20 mA/HART 4-wire
Power supply and signal current are carried on two separate connection pairs of
wires.
4.2.1
Connection Cable
•
Use a 8…12 mm diameter cable to ensure the seal effect of the cable entry
•
Conductor size of minimum 22AWG, shielded twisted pairs
•
Suitable for application (indoor or outdoor) and safety certified according to
national rules.
4.3
Connection procedure
1.
U
nscrew the back cover
2.
L
oosen the compression nut of the cable entry.
3.
R
emove approx
.
10 cm
(
4 inch
)
of the cable mantle
,
strip approx
.
1 cm
(
0
.
4 inch
)
insulation from the ends of the individual wires.
4.
I
nsert the cable into the sensor through the cable entry.
5.
Push the terminals top with a screwdriver
(
see following illustration
).
6.
I
nsert the wire ends into the open terminals according to the wiring plan.
7.
Let go of the terminal top
.
8.
C
heck the hold of the wires in the terminals by lightly pulling on them.
