Westermo RFR-212-FB - Manual (Page 13)

13 6641-2223
By-Pass functionality
The by-pass functionality in RFR-212-FB secures connection in case of power failure in
one of the switches. If a switch has power loss an internal relay in RFR-212-FB will by-
pass the switch and bridge two Ethernet ports.
By-pass interfaces
In case of power failure X9 will be by-passed to X11 and X10 will be by-passed to X12.
Internally the switch will bypass
X9.1
Connected to
X11.2
X9.2 X11.1
X9.3 X11.4
X9.4 X11.3
X10.1 X12.2
X10.2 X12.1
X10.3 X12.4
X10.4 X12.3
Note! When by-passing a switch, approximately 5 m (16.4 ft) of the transmission range
(100 m, 328 ft) is consumed. As an example, if a network is intended to cope with a
single car blackout scenario and that two RFR-212-FB in that case will be by-passed, the
total cable distance through the blackout car to adjacent switches on each side of the
blackout car, should not exceed 90 m. (295 ft) Normally, RFR-212-FB can handle longer
distances, up to 150 m (492 ft), but this can not be guaranteed and has to be investigated
case by case. Cable length data is valid for cat5e cable.
X11
X12
X10
X12
X11
X9
X10
X9
Switch 1 Switch 2 Switch 3