DIP Switches
The DIP (dual
that are printed in a convenient reference key alongside the switches. NOTE: A DIP switch reference list is also listed in the product’s Specifications. In the example at right (model 515344), DIP switches 6 and 7 enable the Local Loopback (LLB) and
Remote Loopback (RLB) diagnostic functions (see Loopback Testing).
Loopback Testing
On some models (see Specifications), DIP switches let you activate both local and remote loopback diagnostic test functions. Check for proper cable connections first, and run the test with a traffic level of at least 50 percent of capacity to optimize the brightness of the LED indicators. Don’t conduct both loopback tests at the same time.
Local Loopback
Use a local loopback (set the designated DIP switch to On to enable) to check that the copper segment is connected properly. Launch a loopback or diagnostics testing program (see NOTE below) and follow the program instructions. Typically, the instructions will be similar to the following:
1. Enter the number of test messages (frame packets) to be sent
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