FMC Corporation - Talstar 80 - Handbuch (Seite 33)

Proline Promass 80 PROFIBUS PA Wiring
33
Technical data (fieldbus connector):
Shielding of the cable connection/T-box
Use cable glands with good EMC properties, with surrounding contact of the cable gland (iris
spring). This requires small differences in potential, and possibly potential matching.
• Do not interrupt the shielding of the PA cable.
• Always keep the connection of the shielding as short as possible.
Ideally, cable glands with iris springs should be used for the connection of the shielding. The shield
is placed on the T-box via the iris spring that is inside the cable gland. The shielding mesh is located
under the iris spring. When the PG thread is screwed closed, the iris spring is pressed onto the
shield, making a conductive connection between the shielding and the metal housing.
A junction box or connection is to be considered part of the shielding (Faraday cage). This is
particularly true for offset boxes when these are connected to a PROFIBUS PA measuring device
using a plug-in cable. In such a case, use a metallic plug in which the cable shielding is attached to
the plug housing (such as prefabricated cables).
Connection cross section 0.75 mm 2
Connector thread PG 13.5
Degree of protection IP 67 in accordance with DIN 40 050 IEC 529
Contact surface CuZnAu
Housing material Cu Zn, surface Ni
Flammability V - 2 in accordance with UL - 94
Operating temperature –40 to +85 °C (–40 to +185 °F)
Ambient temperature –40…+150 °C, (–40… +302 °F)
Nominal current per
contact 3 A
Nominal voltage 125 to 150 V DC in accordance with the VDE Standard 01 10/ISO Group 10
Resistance to tracking KC 600
Volume resistance
≤ 8 mΩ in accordance with IEC 512 Part 2
Insulation resistance ≤ 10 12 Ω in accordance with IEC 512 Part 2