Measuring single mode fiber links with embedded APC connectors

Problem

APC connections produce non reflective OTDR events and are consequently evaluated as splices, most likely generating false failures.

Solution

Initial result

During OTDR testing of a single mode link with APC connections, you may need to change the event type.

Following picture shows the EventMap of a link with three connections.

Note that the embedded connection is interpreted as a splice.

Depending on the splice loss settings, this may have caused a false failure (in this case it doesn't as the limit was set to 0.30dB).

In any case, this EventMap and consequently the EventTable are incorrect.