FCM 300 / FCD 300 / VLT
®
2800 / DP V1 PROFIBUS
The bus termina tion - FCM 300
1 = RxD/TxD-P∼ (red cable) 2 = RxD/TxD-N∼ (green cable)
It is essential that the bus line is terminated properly.
A m is match of impedance may result in reflections
onthelinethatwillcorruptdatatransmission.
- The PROFIBUS is provided with a suitable
termination which may b e activated by the switches
of the RS485 switch block located just to the left of
the terminal block X100 (see drawing below ). The
switches s hould be on to term inate the b us.
NB!:
The switches should never be left in opposite
positions. They should either both be
ON or both be OFF!
- Most masters and repeaters are equipped
with their own termination.
- If an external termination circuit consisting of three
resistors is connected to the bus line a 5 V d.c.
power supply m ust be used, please note that this
must be galvanically isolated from the a.c. line.
MG.90.A5.02 - VLT is a registered Danfoss trademark
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