DACS App Note

Remote Interface Unit Diagnostic Testing Using Model Builder Utility 'RIUTEST' (#49)

Appendix A: Quick Guide To TDM and RIU Troubleshooting

TDM Card & General DACS Node Info

Check page 1 of 3 on the Waveform DSP/Times page. A healthy TDM card is indicated by:

• Running DSP frame counter
• DSP spare time > 0
• Running instruction counter
• Running timer

PROBLEM

Error message: "Interrupt Jumper Missing"

SUGGESTION

Reset the main node by pressing the front panel Reset button. If the error message persists, contact ASTi support.

PROBLEM

Error message: "DSP1 (or DSP2) Failed at Startup"

SUGGESTION

Reset the main node by pressing the front panel Reset button. If the error message persists, contact ASTi support.

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RIU/General

A healthy TDM ring is indicated by:

• All RIUs on the ring show green lights, flashing at a once-per-second rate, and
• The correct RIU address is shown on the Waveform DSP/Times/RIU Present page in Model Builder.

PROBLEM

No lights are illuminated on one or more of the RIUs.

SUGGESTION

Ensure that: the RIU power supply is securely mated to the RIU, the detachable AC cord is securely mated to the power supply and that AC power (110 to 240 VAC, 50/60 Hz) has been applied to the power supply. Substitute power supply or AC cord as necessary to isolate and correct faults.

PROBLEM

The RED lights are illuminated on all RIUs.

SUGGESTION

• The main node is not running. Start the system, inspect the Error page and fix any error messages (see DACS O&M Manual).
• The TDM cables are faulty. The main node is running, but the necessary signals are not being sent to the RIU. Check the first cables in the TDM ring between the RIU and the DACS.

PROBLEM

The RED and GREEN lights are both lit.

SUGGESTION

Press the RIU Reset button located on the front faceplate.

PROBLEM

The GREEN light on one or more of the RIUs is blinking at a fast rate (about 4 times per second).

SUGGESTION

Possible causes include: incorrect model running on the main node, one or more of the RIUs is incorrectly addressed, or there is one or more faulty TDM cables in the ring.

1. Inspect the Error list for error messages. Make corrections as needed.
2. Ensure that the RIU switch addresses match the addresses in the custom model RIU Feeder objects.
3. Ensure that all of the Category 5 TDM cables are correctly installed and securely mated at each connector on the RIUs and the TDM card. (RIU v4.1 Tech Guide)
4. Check the Category 5 TDM cables, substitute with spare cables to isolate faults, then restart the system.

NOTE: RIU lights can indicate the location of a TDM ring fault. For example: if RIU 1 and RIU 2 both have slow blinking GREEN lights and RIU 3 has a fast blinking GREEN light, there is most likely a faulty cable between RIU 2 and RIU 3 -OR- RIU 3 is addressed incorrectly.

PROBLEM

The GREEN lights on all of the RIUs are flashing once per second, but not all of the correct RIU addresses are displayed on the Waveform DSP/Times/RIUs Present page.

SUGGESTION

1. Ensure that all of the Category 5 TDM cables are securely mated at each connector on the RIUs and the TDM card.
2. Check the Category 5 TDM cables, substitute with spare cables to isolate faults, then reset all RIUs and restart the system.