Installation and Troubleshooting 2- 11
Installing the ONline System Concentrator
The ONline System Conc entrator can be placed on top of a table or a she lf,
or mounted in a rack. Make sure the ca ble tray has been installed first on
the table or in the rack (or that 1 3/4" (4.5 cm ) of vertical space has been
provided below the unit for air flow) an d that the location meets all the
environmental consideratio ns specified earlier in this chapter.
Caution: 3Com recommends that two people install the unit
since it weighs 38 lbs (17 kg) with one power supply
and 46 lbs (24 kg) with the backup power supply
installed.
3Com also recommends installing the backup po wer supply
prior to rack mounting the unit (see the section titled
Installing the Backup Power Supply later in this chapter). In
some rack cabinets, the rear of the cabinet may interfe re
with installation or removal of the power sup pl y and fan.

Rack Mounting the ONline System Concentrator

The ONline System Conce ntrator can be mounted in fou r different
configurations in the rack. Us e the same rack settings for both the cable
tray and the concentrator. If you are not installin g the cable tray in the
rack, you should select the concentrator mount settin g at this time. Refer
to Table 2-2 and Figure 2-2 in the “Cable Tray Rack Mounting” section fo r
specifics about the four mounting settings.
Follow the steps below to mount the co ncentrator in your rack:
1. Attach the two rack moun t flanges to the ONline conc entrator unit in
the position you want as shown in Figure 2-4 using the eight (8)
provided 8-32 x 1/4" flathead screw s - four per side.