MicroNet Technology SP3508A - Manual (Page 44)

7.3 Appendix C: System Diagnostics
7.3.1 Power and Cooling Problems
If the POWER indicator does not turn on when the power cord is plugged in,
users may have a problem with the power outlet, power cord, or internal
power supply as explained in the previous section. However, if the unit should
turn itself off after running for a while, check for loose power connections,
power loss or surges at the power outlet, and verify that the fan on back of
the unit is unobstructed and running prior to shutdown. If you still cannot
isolate the problem, then the internal power supply may be defective. In this
case, contact the supplier for assistance.
7.3.2 Installation
Verify that all system components have been properly installed. If one or
more components appear to be malfunctioning (e.g., the power cord or
network cabling), then test them in an alternate environment where you are
sure that all the other components are functioning properly.
7.3.3 Transmission Mode
The selections of the transmission mode for the RJ-45 ports are auto-
negotiation using the default method. Therefore, if the Link signal is disrupted
(e.g., by unplugging the network cable and plugging it back in again, or by
resetting the power), the port will try to reestablish communications with the
attached device via auto-negotiation. If auto-negotiation fails, then
communications are set to half duplex by default. Based on this type of
industry-standard connection policy, if users are using a full-duplex device
that does not support auto-negotiation, communications can be easily lost
(i.e., reset to the wrong mode) whenever the attached device is reset or
experiences a power fluctuation. The best way to resolve this problem is to
upgrade these devices to version that will support auto-negotiation.
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