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2
Card Connections and Installation
2-1
2.1
Introduction
WARNING
The following connection and installa-
tion procedures are to be performed by
qualified service personnel. Failure to
recognize and observe standard safety
precautions could result in personal in-
jury or death.
NOTE
All input and output channels are electri-
cally isolated from the backplane of the
mainframe.
2.2
Internal connections
NOTE
All internal connections are for the digital
outputs. No internal connections are re-
quired for reading digital input channels.
The Model 7020 is made up of two PC-boards that plug to-
gether and are secured together by a 4-40 screw. To gain ac-
cess to internal connections, remove the screw and carefully
separate the two boards. The board with the 96-pin DIN con-
nector is called the mass terminal board, and the board with
the majority of components is called the scanner board.
2.3
Voltage source jumpers
Digital output high can be supplied by the internal 5.3V volt-
age source, or by a user supplied voltage. At the factory, in-
ternal jumpers are set to use the internal 5.3V source.
The 40 output channels are divided up into fi e banks (eight
output channels per bank) as shown in Figure 2-1. For each
bank, there is a plug-in jumper that allows you to select the
internal 5.3V source or an external source. In Figure 2-1,
Banks B, C and D use the 5.3V source, while Banks A and E
use an external source.
The I/O card can accommodate two different external volt-
age sources (V
EXT1
and V
EXT2
) by removing (cutting) jump-
er W105 (see Figure 2-1). With W105 removed, the external
voltage source (V
EXT1
) for Banks A, B and C is electrically
isolated from the external voltage source (V
EXT2
) for Banks
D and E.
The voltage source jumpers are located on the scanner board
as shown in Figure 2-2. Figure 2-3 shows how the plug-in
jumpers (W100 through W104) are installed.