Racal Instruments 1266, Руководство пользователя

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2-20 Installing Mainframe Options Chapter 2
Installing Intermodule Chassis Shields
This section describes how to install Option 52, Intermodule Chassis Shield
Kit, (P/N 407870-003) in the 1266 mainframe. The chassis shield is the
implementation of VXI revision 1.4, specification B.7.3.4 that allows
grounded shielding between mainframe slots. The shield is used to isolate
VXI modules that generate electromagnetic interference (EMI) at excessive
levels, or to protect VXI measurement modules from noise sources.
WARNING
Do not install intermodule chassis shields while the mainframe
is turned on or plugged into an AC power source.
Parts List
The parts included in the Option 52 (P/N 407870-003) kit are shown in Table
2-4.
Installation
Procedure
Each mainframe slot has top and bottom chassis shield guides (Figure
2-19). Chassis shields should be installed on both sides of an instrument
generating interference/noise, or installed on both sides of a sensitive
instrument.
1 Insert Grounding Springs . Insert grounding springs into the four
sockets (two top, two bottom) along the shield guides. Use a small flat
blade screwdriver to secure each spring under the socket tab.
NOTE Use the chassis shield to cover the vent holes inside the mainframe when
installing grounding springs in the top guide sockets. This prevents the
springs from falling into the mainframe if they are accidently dropped.
2 Install the Chassis Shield. Align the chassis shield with the shield
guides and gently slide the shield into the mainframe. Be careful not
to crimp the front grounding springs with the edge of the shield. Slide
the shield in until it reaches the end of the shield guide.
Table 2-3. Option 52 Parts List.
Quantity Description
1 Chassis Shield
8* Grounding Spring
* Includes 4 extra springs.