Allen-Bradley MediaChecker 1788-MCHKR Manual page 25

When the MediaChecker detects something on the far
end of the cable, but cannot determine if it is the Cable
ID, "ID" is displayed. The MediaChecker alternately
displays "??" and "RA" when the Cable ID is detected but
a problem with the cable or with the Cable ID is interfering
with the identification process.
Without the Cable ID connected to the far end of the
cable, the MediaChecker displays "--".
Testing the Wire Map (WIRE MAP)
The following display indicates the near end wiring of a
cable without the Cable ID connected:
Table 11 shows example of wire map failures on
DeviceNet cable.
aan14f.eps
1788-UM002A-US-P – April 2000
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