BERTHOLD TECHNOLOGIES LB 3602, Руководство по эксплуатации

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LB 379
18
4 Electrical Connections
4.1 Detector
Switch off the evaluation unit before connecting the detector.
Open the screws and remove the connection box cover to expose the connection area.
For intrinsically safe installations, connect the detector to the potential equalization bar of
the installation. The detector is connected to the evaluation unit via a 2-wire cable with
approx. 8
…
10 mm diameter and a cross-section
of 1 mm². A screen cable may be used in instal-
lations with extremely strong electrical interfer-
ences. The screen may be placed only on one
side of the detector.
Figure 7: Cable connections to the detector
For intrinsically safe installations, the per-
missible inductivities and capacities of the
connection cable have to be observed in ac-
cordance with the Ex test certificate.
Please observe the maximum cable lengths be-
tween evaluation unit and detector. They are
listed in chapter 5.
When installing the connection cable, make sure that water cannot get into the connection
box via the cable. At ambient temperatures >70°C, the installed cable has to be protected
to prevent exceeding of the temperature limits of the cable. After connecting, make sure
that the terminal compartment is carefully closed and the cable conduit properly sealed.
If a resistance thermometer is connected, pass the cable coming from the Pt 100 through
the second cable conduit to the terminals 3 and 4.
For installations in hazardous areas, the special requirements of the cable and to
the preparation of the lines have to be observed.
The detector LB 44... has to be used for installation in hazardous areas. Detector
LB 54.. may only be used for non-hazardous applications.
The evaluation unit must always be installed outside the hazardous area.
A special transmission technique ensures interference suppression. Nevertheless, the cable
should not be installed together with power cables.
4
3
2
1
5
LB 444
PA
Pt 100
LB 47x