705-5100-F21 Datasheet, PDF (38/52 Pages) Magnetrol International, Inc. – Enhanced Model 705 with PROFIBUS PA™ Digital Output

7.1.3 Error Mapped to Diagnosis (cont.)
Note that PV status for Interface and Volume process vari-
bles may indicate a configuration error if the correct
Measurement Type has not been selected. In this case,
“Configuration not valid” will not be set in the DIAGNO-
SIS parameter since level measurement may still be correct.
Also, a Default Parameters Fault is indicated after a Factory
Reset which will result in the DIAGNOSIS indication
“Configuration not valid”.
7.1.4 PROFIBUS PA^TM Segment Checklist
There can be several reasons for a PROFIBUS PA^™ installa-
tion to be in a faulty condition. In order to assure that com-
munication can be established, the following requirements
must be met.
• Device supply voltage must be higher than 9 VDC with a
maximum of 32 VDC.
• Total current draw of a given segment cannot exceed the
rating shown on the power conditioner and/or barrier.
• Device polarity must be correct.
• Two 100 Ω, 1 µF terminators must be connected to the
network—one at each end of the segment.
• Cable length plus spur length must not exceed the following
values:
Number of Spurs
25–32
19–24
15–18
13–14
1–12
1 Device
2 Devices
—
—
100 ft. (30 m)
—
200 ft. (60 m) 100 ft. (30 m)
300 ft. (90 m) 200 ft. (60 m)
400 ft. (120 m) 300 ft. (90 m)
3 Devices
—
—
—
100 ft. (30 m)
200 ft. (60 m)
4 Devices
—
—
—
—
100 ft. (30 m)
Pair
Single
Multi
Multi
Multi
Shield Twisted
Yes
Yes
Yes
Yes
No
Yes
Yes
No
Size
AWG 18 (0.8 mm2)
AWG 22 (0.32 mm2)
AWG 26 (0.13 mm2)
AWG 16 (1.25 mm2)
Length
6,200 ft. (1,900 m)
3,900 ft. (1,200 m)
1,300 ft. (400 m)
650 ft. (200 m)
Type
A
B
C
D
• The cable shield is to be hard grounded only at one point
close to the DCS. In addition, the cable shield can be
capacitively grounded in multiple places to improve EMC
protection.
If all of these requirements are met, a stable communication
should be established.
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57-645 Eclipse Guided Wave Radar Transmitter - PROFIBUS PA^™