Chapter 7
If the power supply operates normally, you probably have either a shorted device or a shorted cable. If the power supply does not operate normally, then test for a module causing the problem by using the following procedure.
To isolate which module is causing the problem, disconnect the external power and remove one module at one time till the PWR LED operates normally. Follow the procedure below:
1.Turn off power to the base.
2.Remove a module from the base.
3.Reapply power to the base.
RUN Indicator
If the self test for the system has passed, the RUN LED is still on except no power.
7.4Communication Problems
If you cannot establish communications with the system module, check these items:
•The cable is disconnected
•The cable has a broken wire or has been wired incorrectly
•The cable is improperly terminated or grounded
•The device connected is not operating at the correct baud rate
•The device connected to the port is sending data incorrectly
•A grounding difference exists between the two devices
•Electrical noise is causing intermittent errors
•The system module has a bad communication port and it should be replaced
