IBM 1PA, Руководство по эксплуатации, установке и обслуживанию

Страница: 49 / 108

Figure 3-1. Power Connections for Models 2EX and 2FX
b. Plug the other end of the AC power cord into the power outlet.
When you power on a model 2EN, 2EX or 2FX, a lamp test is performed.
Verify that all the LEDs light for about two seconds before fading to black.
8. Power on all the devices.
Changing the Hub Polarity and Pinout Jumpers
The polarity and pinouts are factory set. If the polarity and pinouts match the hub
defaults, you do not need to change the jumpers. Using consistent polarity and
pinout throughout the network is recommended.
If you change your cabling scheme or if the polarity and pinout of existing cabling
are inconsistent, you can change the polarity and pinout of the 7299:
Ÿ
RJ11 connectors are shipped with pins 2 and 5 active, normal polarity. You
can configure pins 3 and 4 to be active instead.
Ÿ
RJ45 connectors are shipped with pins 4 and 5 active, normal polarity. You
can configure pins 1 and 2, or pins 3 and 6 to be active instead.
To change the polarity and pinout:
1. For models 2EN, 2EX and 2FX, disconnect all power to the 7299.
2. Remove the two screws that are on the rear panel.
3. Slide the top cover of the 7299 back about 2.5 cm (1 in).
Chapter 3. Installing the 7299
3-3