Endress+Hauser iTEMP TMT85, Руководство по эксплуатации

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Electrical connection iTEMP TMT85
18 Hauser
Item B, fine-strand wire without ferrule:
1. Strip wire end. Min. stripping length 10 mm (0.39 in).
2. Press down on the lever opener.
3. Insert the wire end into the terminal.
4. Release lever opener.
5. Pull the wire gently to ensure it is connected correctly. Repeat from step 1 if
necessary.
Item C, releasing the connection:
1. Press down on the lever opener.
2. Remove the wire from the terminal.
3. Release lever opener.
5.2.2 FOUNDATION Fieldbus TM cable specification
Cable type
Twin-core cables are recommended for connecting the measuring device to the
FOUNDATION Fieldbus TM H1. Following IEC 61158-2 (MBP), four different cable types
(A, B, C, D) can be used with the FOUNDATION Fieldbus TM , only two of which (cable types
A and B) are shielded.
• Cable types A or B are particularly preferable for new installations. Only these types have
cable shielding that guarantees adequate protection from electromagnetic interference
and thus the most reliable data transfer. In the case of cable type B, several fieldbuses
(same degree of protection) may be operated in one cable. No other circuits are
permissible in the same cable.
• Practical experience has shown that cable types C and D should not be used due to the
lack of shielding, since the freedom from interference generally does not meet the
requirements described in the standard.
The electrical data of the fieldbus cable have not been specified but determine important
characteristics of the design of the fieldbus, such as distances bridged, number of users,
electromagnetic compatibility, etc.
Type A Type B
Cable structure Twisted pair, shielded One or more twisted pairs, fully shielded
Wire size 0.8 mm 2 (18 in 2 ) 0.32 mm 2 (22 in 2 )
Loop-resistance (direct current) 44 Ω/km 112 Ω/km
Characteristic impedance at 31.25 kHz 100 Ω ±20 % 100 Ω ±30 %
Attenuation constant at 39 kHz 3 dB/km 5 dB/km
Capacitive asymmetry 2 nF/km 2 nF/km
Envelope delay distortion (7.9 to 39 kHz) 1.7 mS/km *)
Shield coverage 90 % *)
Max. cable length (incl. spurs > 1 m (3 ft) 1 900 m (6 233 ft) 1 200 m (3 937 ft)
*) Not specified
Suitable fieldbus cables (type A) from various manufacturers for non-hazardous areas are
listed below:
• Siemens: 6XV1 830-5BH10
• Belden: 3076F
• Kerpen: CeL-PE/OSCR/PVC/FRLA FB-02YS(ST)YFL