TC Communications TC8916, User Manual

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MNL-89160-05-03
The RJ-11 cable connectors and DB25 connector are frequently the source of various problems. Check out
the connectors, cable, and pin connections first. Once installation of the TC8916 is complete, it is a good idea
to perform a Local Loopback test to verify that the TC8916 is working properly.
The purpose of this test is to verify the input/output connections, signal input receiver, and signal output driver
of the unit. See step #3 below on bench testing.
The electrical signal injected to pin 5 (TxD) will be looped back to pin 4 (RxD). This loopback is formed inside
the TC8916, after the input signal is translated to a TTL signal format.
It is highly recommended to conduct bench tests before actual installation. Bench testing allows the user to
become familiar with all the functions and features of the TC8916 in a controlled environment. Knowledge
of the TC8916's functions and features will facilitate installation and troubleshooting efforts later on.
1. Follow steps 1 through 4 from the system startup section on page 13.
2. At step 5, use a BERT (Bit Error Rate Tester) Test Set or other device that will send an RS-232 or RS-
422 signal to the RJ-11 MAIN Port on the TC8916.
3. Perform a Local Loopback test by setting the "LOCLB" DIP switch (SW1_2) to the down "On" position.
Verify that the "MAIN," "BRD," & "RSP" LEDs light solidly. Verify that the tester or other device is
correctly receiving the loopbacked signal.
Return SW1_2 to the up "Off" position when done with the test .
4. Implement the setup of the devices as you will be using them in the field. Plug in your RS-232 or RS-
422 source into the TC8916's MAIN Port (CH1). Plug in one of the RTU devices (that you intend to
broadcast to) into the RJ-11 Port 2 (CH2). You should see the "MAIN" LED and "RSP & BRD" LEDs
of the corresponding CH2 lit, indicating that the signal is correctly broadcasted and received.