Rosemount TankRadar Rex DAU 2100, Руководство по обслуживанию

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Rosemount Tank Radar Rex
Chapter 4 Service
4-70
Service Manual
308012En, Ed.2
May 2013
In order to allow proper operation and to fulfil EMC requirements, the
cable between the RDU 40 and the Rex junction box should meet the
following requirements:
• Shielded cable. Minimum 3 wires. The shield shall be circular con-
nected inside the cable gland of the RDU 40 and connected to
ground in the Rex junction box.
• All wires must have at least 0.25 mm individual insulation.
• Maximum total length of 100 m, both master and slave included.
• Minimum AWG 20 or 0.5 mm² for each wire.
The RDU 40-chassis shall be grounded locally to the tank. Use minimum
4 mm² or AWG 11 wire. Additional protective ground connection to the
power distribution central or the Rex junction box is not recommended
except where required according to national code of practice. A ground
loop with circulating current may occur.
Note! It is not possible to use an RDU40 and a DAU simultaneously.
If a cable with two shields is used, one shield shall be connected to
ground in the Rex junction box and the other shall be circular connected
inside the cable gland of the RDU 40.
Check the gasket and put the locking device for the weather protection
hatch in position when remounting the RDU-cover. Tighten all six screws
firmly.
Mount the RDU 40 with the four M4 screws. Distances between the
screws are 60 mm and 68 mm according to the back of the RDU 40.
See the RDU 40 User´s Guide, Ref. no. 308010E, for further
information on RDU 40 installation.
Figure 4-36. Back of RDU40.