TMT84 Wiring
Endress+Hauser 15
!
Note!
When connecting flexible wires to spring terminals, it is not recommended to use ferrules.
4.3 PROFIBUS
®
PA cable specification
4.3.1 Cable type
Twin-core cables are required for connecting the device to the fieldbus. Following IEC 61158-2
(MBP), four different cable types (A, B, C, D) can be used with the fieldbus, 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 protec-
tion) 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 de-
scribed in the standard.
The electrical data of the fieldbus cable have not been specified but determine important character-
istics of the design of the fieldbus, such as distances bridged, number of users, electromagnetic com-
patibility, etc.
Suitable fieldbus cables from other manufacturers for non-hazardous areas are listed below:
• Siemens: 6XV1 830-5BH10
• Belden: 3076F
• Kerpen: CeL-PE/OSCR/PVC/FRLA FB-02YS(ST)YFL
Item C and D
Releasing the connection:
1. Operate lever opener with tool (C).
2. Remove wire from terminal (D).
3. Release lever opener.
Type A Type B
Cable structure Twisted pair, shielded One or more twisted pairs, fully
shielded
Wire size 0.8 mm
2
(AWG 18) 0.32 mm
2
(AWG 22)
Loop-resistance (direct current) 44 /km 112 /km
Characteristic impedance at 31.25 kHz 100 ± 20% 100 ± 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 >1m/3ft) 1900 m (6233 ft) 1200 m (3937 ft)
* Not specified
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