connected as a dual 16-channel single-ended multiplexer.
SECTION 1. INSTALLATION
There are 40 terminals on the Model 17B. Because so many
electrical connections must be made, it is advisable to proceed
carefully. Labeling all wires will save time in the end.
Eight wires will be needed to connect the Model 17B to the
A/D card. See the appropriate section in the A/D card's manual
for pin locations. The interconnecting wire can be of any
general-purpose type. We strongly recommend shielded wire for all
connections. Small diameters and long lengths of wire will not
interfere with system function except in extreme cases. For
example, 50 feet of 26AWG shielded wire will not significantly
affect the system. The "+" output should connect to one of the
plus input pins on the A/D's connector and the "-" output should
connect to the corresponding minus input at the A/D card. The
examples in this manual assume the first Model 17B is connected
to input #0. If another input is used, the control codes should
be adjusted as described in the A/D manual. The ground terminal
(G) on the Model 17B should be connected to chassis ground at the
computer.
WARNING: Use a cover-securing screw (without paint) for chassis
ground.
On some portable computers, no metal chassis contact is
accessible. In that case, use the center screw of the power
outlet as ground. We do not recommend using the ground pin on the
A/D card connector instead of chassis ground because it is
possible that under certain catastrophic conditions the ground
current might be large enough to cause damage to the computer.
The control inputs to the Model 17B should now be connected
to the isolated control output lines on the A/D card connector.
Input A is connected to output A on the A/D, input B is connected
to output B on the A/D, input C is connected to output C on the
A/D, and input D is connected to output D on the A/D card.
Connect the Guard pin on the A/D card connector to the G terminal
on the Model 17B.
NOTE: There should now be two separate wires from the computer
connected to the G terminal of the Model 17B.
FIGURE 1. TYPICAL INTERCONNECTIONS