Future Design MCT-MC 4.3, Руководство пользователя

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MCT-MC
4.3
Offline Setup - 127 - FDC MCT-MC
The most commonly overlooked source of problems is cabling. Not all cables are created equal. Electrical
noise generated by factory equipment or other electrical equipment in the area, could easily corrupt transmitted
data over the network and cause devices to “lock up” or shut down the VNC server, both of which then require
the MC to be shut down and restarted to clear the problem.
Select the right cable for the environment. Shielded twisted pair (STP) cable is naturally more noise immune
and is preferable to unshielded twisted pair or UTP in noisy situations. STP should have at least 40dB CMRR
and less than 0.1pF capacitance unbalance per foot. Ground STP cable, making sure the ground is connected
only at one end. CAT5 STP patch panels normally provide a grounding strip or bar. Hubs and switches don’t
provide grounding, use cables.
It’s wise to be pessimistic about a cable’s ability to reject noise from 230 VAC and 460 VAC power lines and
electrically “noisy” equipment in the area. Capacitance imbalance in cables greater than 70pF per 100m can
introduce harmonic distortion resulting in bit errors. The cost of cable is quite small compared to total equipment
cost, so if you’re looking to save money, this is not a place to do it. Choose a well designed cable to minimize
bit-error rate after installation, and that will give faster throughput with fewer glitches.
11.1.2 Configuring the MC Network
In order to connect to the VNC server or web server of the MC, you will need to know the IP address of the MC
on the network. It is important to note that if using DHCP in your network router, the MC address may change
on re-power requiring you to access the MC controller directly in order to obtain the new IP address. This could
result in VNC/web server connection issues if the address regularly changes.
Therefore, it is recommended that the IP address for the MC be assigned as a fixed (static) address. This
insures that the address will not change once it has been set. This can be done in one of two ways. The first
is by setting up the control LAN router to assign the same IP address whenever it detects the MC device on the
network via its own identifier; it’s MAC address.
The other option is to configure the MC to use a fixed IP address and disable the DHCP addressing function of
its network interface. When using this method, it is important to make sure that the address being assigned to
the MC is not used by any other device on the network. If another device is using the same address, the VNC
and web server interfaces will not function correctly. It is recommended that this method of static IP assignment
be used as it removes the IP address lease renewal process that would be performed by the control LAN router
if DHCP was used.
The lease renewal process performed by the control LAN router can cause the VNC server in the MC to shut
down due to an issue in the renewal process. It could be caused by something in the router firmware or
configuration of the router itself. Due to the numerous brands and models of routers available, and the dynamic
nature of their use, attempting to resolve the issue is beyond the scope of this manual. Therefore, the use of
static IP addressing removes this from the equation, providing the most robust network solution.
11.1.2.1 Obtaining the MC MAC Address
The MAC address can be obtained from the network connections screen. In order to access the screen, you
must exit the MC application. To do so, proceed to the “Exit Application” screen under the offline setup menu.
Press the “Exit and start runtime on next power up” button to exit the MC runtime application. Follow the on
screen prompts to stop the application and exit to the Windows CE desktop.
NOTE: The text, “System Startup Please Wait…” on the desktop is static and does not indicate that any
application is going to start at this time. It is used as a placeholder prior to the MC runtime or
configuration application starting during normal power-up sequences so that the user is informed that
an action is taking place.