Technical Manual

Technical Manual RF Mono
Connections v1.4 Page 12 of 47
5.4 Field Bus termination
For the Field Bus to operate properly, the bus needs to be terminated on the first device
and the last device in the bus.
When an antenna is either the first or the last device in the Field Bus, then the bus needs
to be terminated on that device.
To terminate the RFM antenna, switch SW1 must be switched to ON. See chapter 5.6 for
the position of this switch on the RFM PCB.
Figure 3: Field Bus termination example during local service or installed CCAP
In case the Access Point is only temporarily connected during installation or local service,
the first device in the row must be terminated after the CCAP is disconnected again.
Figure 4: Field bus termination after CCAP is disconnected
RFM1
Field bus
UTP
UTP
UTP
UTP
CrossCONNECT
Access Point
RFM2
RFM3
RFMx
Terminate Field bus
on the last device
Field bus is
automatically terminated
on the Access Point
RFM1
UTP
UTP
UTP
RFM2
RFM3
RFMx
Terminate Field bus
on the last device
Terminate Field bus
on the first device