
Installing the Encoder
Powering Up the Unit
Makito X User’s Guide, v2.0, Issue 01
57
MB21B (21-Slot) Chassis
WARNING
To prevent electric shock, do not remove the cover of the MB21B chassis.
There are no user-serviceable parts inside. The MB21B chassis is to be installed and
serviced by qualified personnel only.
Figure 2-12
MB21B Chassis Rear View showing Power Connectors
Each socket on the PDU (Power Distribution Unit) powers a pair of PSUs (Power Supply
Units). Two PSUs are sufficient to power a fully loaded chassis.
The MB21B chassis is designed to tolerate the following without loss of installed card func-
tionality:
•
The loss of one AC supply (120/240V) source.
Since there are two power inlets on the MB21B chassis, the cards in the chassis can
operate with only one powered; however, the chassis would not be fully redundant.
•
The loss of one or two PSUs of the four PSUs in the MB21B chassis in any
combination.
To power up the MB21B Chassis:
1.
Turn all four PSU Power On/Off switches to the ON (1) position.
2.
Connect the power cords to both power receptacles.
3.
Plug both cords into earthed AC power sources.
PSU Power On/Off Switches
AC Power
PSU Alarm LED (red)
PSU Alarm Reset
Receptacles
PSU Status LED
(green)
button