Samson 3785 series, Монтаж и эксплуатация

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Note on the selection of cables and wires:
To run several intrinsically safe circuits in a
multicore cable, note section 12 of EN
60079-14; VDE 0165/8.98.
In particular, the radial thickness of commonly
used materials, e.g. polyethylene, for the con-
ductor insulation must be minimum 0.2 mm.
The diameter of a single wire in a flexible con-
ductor must not be smaller than 0.1 mm.
The conductor ends must be protected
against unlaying, e.g. by using wire end fer-
rules. If the positioner is connected via 2
separate cables, an additional cable gland
can be mounted.
Wire entries left unused must be sealed with
caps.
Positioners used in ambient temperatures
down to
−
40 °C must be fitted with metal
cable entries.
For the terminal assignment, refer to Fig. 9
or to the cover plate inside the case cover.
Bus line
The shielded PROFIBUS connecting cable
must be routed over the EMC-proof brass
cable gland (standard) of the positioner to
the terminals. The shield, which is placed
over the clamping insert, is connected over
a large area to the gland and housing.
1. To connect the bus line, loosen the coup-
ling nut and the clamping insert from
the positioner and remove the dust cap.
2. Slide the coupling nut and clamping in-
sert over the connecting cable.
3. Strip the insulation off the end of the
bus line to the required connecting
length and cut the wire shield off up to
a length of approx. 13 mm. If necess-
ary, cut off any cable core filling as
well.
4. Disentangle the braided shield and pull
it over the clamping insert.
5. Press the clamping insert into the con-
necting screw gland and screw tight the
coupling nut until the connecting cable
is clamped tightly.
6. Route the two-wire bus line to the screw
terminals marked "EN 61158-2",
whereby no polarity has to be observed.
In exceptional cases, when the plant may
not allow such a connection, feed the cable
shield through the cable gland and connect
it to be capacitive over the terminal "S".
However, make sure that no conducting con-
nection occurs from the shield to the cable
gland or housing.
26
EB 8382-1 EN
Connections