Endress+Hauser Proline Prosonic Flow P 500, Руководство пользователя

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Proline Prosonic Flow P 500
34 Hauser
Potential equalization Requirements
For potential equalization:
• Pay attention to in-house grounding concepts
• Take account of operating conditions like the pipe material and grounding
• Connect the medium, sensor and transmitter to the same electrical potential
• Use a ground cable with a minimum cross-section of 6 mm 2 (0.0093 in 2 ) for potential matching
connections
For devices intended for use in hazardous locations, please observe the guidelines in the
Ex documentation (XA).
Abbreviations used
• PE: Protective Earth
• P
FL
: Potential Flanges
• P
M
: Potential Medium
Terminals Spring-loaded terminals: Suitable for strands and strands with ferrules.
Conductor cross-section 0.2 to 2.5 mm 2 (24 to 12 AWG).
Cable entries • Cable gland: M20 × 1.5 with cable ⌀ 6 to 12 mm (0.24 to 0.47 in)
• Thread for cable entry:
• NPT ½"
• G ½"
• M20
• Device plug for digital communication: M12
Only available for certain device versions →  26.
Cable specification Permitted temperature range
• The installation guidelines that apply in the country of installation must be observed.
• The cables must be suitable for the minimum and maximum temperatures to be expected.
Power supply cable (incl. conductor for the inner ground terminal)
Standard installation cable is sufficient.
Protective grounding cable for the outer ground terminal
Conductor cross-section ≤2.08 mm 2 (14 AWG)
Grounding impedance must be less than 2 Ω.
Signal cable
Current output 4 to 20 mA HART
A shielded cable is recommended. Observe grounding concept of the plant.
Modbus RS485
The EIA/TIA-485 standard specifies two types of cable (A and B) for the bus line which can be used
for every transmission rate. Cable type A is recommended.
Cable type A
Characteristic impedance 135 to 165 Ω at a measuring frequency of 3 to 20 MHz
Cable capacitance < 30 pF/m
Wire cross-section
> 0.34 mm 2 (22 AWG)
Cable type Twisted pairs
Loop resistance ≤110 Ω/km
Signal damping Max. 9 dB over the entire length of the cable cross-section
Shield Copper braided shielding or braided shielding with foil shield. When grounding
the cable shield, observe the grounding concept of the plant.