
This section describes troubleshooting and check items associated with
the embedded Ethernet function.
1) Is an STP cable used for connection between the hub and embedded
Ethernet?
2) Is the STP cable connected correctly?
In general, a straight cable is used for connection between the hub and
communication device.
3) Is the power to the hub turned on?
4) The PCMCIA Ethernet card is used only with 10BASE–T. Is a hub
for 10BASE–T used when the PCMCIA Ethernet card is used?
5) Is the link LED turned on when the embedded Ethernet port is used?
The link LED is not turned on when the hub is not connected or the
power to the hub is not turned on.
6) Is the LED (for link display) of the connected hub turned on?
(Some hubs are not provided with a link LED.)
The LED is not turned on when the hub is not connected with the
embedded Ethernet or the power to the CNC is not turned on.
This subsection can be ignored when a network is built only with a hub
to which the embedded Ethernet is connected.
The general check items are listed below. For network installation,
consult with vendors specialized in this area. Install cables away from
noise sources.
When a 10BASE–5 backbone is used
1) Are transceivers connected to the backbone cable correctly?
S If the transceivers are connected correctly, the resistance between
the backbone shield and central conductor is about 25 ohms (when
terminating resistors are attached).
S A special tool may be required for transceiver installation. (The
special tool varies from one vendor to another. For details, refer to
the relevant manual of each vendor.)
S At a location where a transceiver was once installed, do not install
a transceiver again. (The backbone cable can be damaged.)
2) Are transceivers installed at correct intervals?
S Transceivers need to be spaced from each other by 2.5 m or more.
It is recommended that transceivers be installed at intervals of an
integral multiple of 2.5 m. Usually, installation locations are
marked on a backbone cable.
3) Are terminating resistors attached?
S A terminating resistor (50 ohms) needs to be attached to each end
of the backbone cable.
8.8
TROUBLESHOOTING
8.8.1
Check Items Related to
Connection with the
Hub
8.8.2
Check Items Related to
Connection with a
Backbone
8. EMBEDDED ETHERNET FUNCTION
GFKE-0222-EN
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