Endress+Hauser PROline Prosonic Flow 93 Serie Fiche Technique page 43

PROline Prosonic Flow 93 PROFIBUS-DP/-PA

Endress+Hauser
Setting the terminators (only by PROFIBUS-DP)
Since mismatches in the impedance result in signal reflections on the line and can thus
lead to communication errors, it is important to terminate the lines properly.
Warning:
Risk of electric shock. Exposed components carry dangerous voltages. Make sure that
the power supply is switched off before you remove the cover of the electronics com-
partment.
The terminator switches are located on the I/O board.
• For baud rates of up to 1.5 MBaud, terminate the last transmitter on the bus by setting
the terminator switch SW 1 to: ON – ON – ON – ON.
• If the device is to be operated at over 1.5 Mbaud, you can tap the supply voltage for
an external terminator from terminals 24 (GND) and 25 (+5 V) (this terminator must be
in conformity with the requirements of the II2G standards).
Fig. 7: Setting the terminators (PROFIBUS-DP)
A = Factory setting
B = Setting on the last transmitter
A
SW 1
ON
O N
OFF
O N
O N
O N
1 2 3 4
1 2 3 4
1 2 3 4
1 2 3 4
+5V
390 Ω 220 Ω 390 Ω


B
SW 1
ON
OFF
+5V
390 Ω 220 Ω 390 Ω
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