VS-2400S 24 Ports VDSL2 Managed IP DSLAM with POTS splitter USER
’S MANUAL Ver.A3
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Appendix C:
Compliance and Safety Information
System Diagnosis
Power and Cooling Problems
If the POWER indicator does not turn on when the power cord is plugged in, you 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 losses 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 your supplier for assistance.
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), test them in an alternate environment where you are sure that all the other components are
functioning properly.
Transmission Mode
The default methods of selecting the transmission mode for all RJ-45 ports are auto-negotiation. 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 you 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 versions
which support auto-negotiation.
