
NATIONAL
INSTRU MENTS
The Software is the Instrument
®
®
Installation Guide
CB-50 Connector Block
This guide describes how to connect your data acquisition board and the CB-50 I/O connector
block to your computer.
Introduction
With the CB-50 I/O connector block, you can easily connect analog/digital signals to the
National Instruments data acquisition boards. You can use the CB-50 with the following boards:
PC/XT, PC AT PS/2 Macintosh
AT-MIO-16 MC-MIO-16 NB-MIO-16
AT-MIO-16F-5 MC-DIO-32F NB-MIO-16X
AT-MIO-16X MC-DIO-24 NB-DIO-32F
AT-AO-6 NB-DIO-24
AT-AO-10 NB-AO-6
AT-DIO-32F NB-TIO-10
AT-DIO-24 Lab-NB
Lab-PC Lab-SE
Lab-PC+
PC-LPM-16
PC-DIO-24
PC-TIO-10
The CB-50 consists of a 0.5 m or 1.0 m ribbon cable and a connector block with 50 screw
terminals. Connector pinout information is in the user manual for each data acquisition board.
At each end, the cable has a keyed connector with a centered tab that you must align with the slot
on the mating header on the connector block or board.
____________________________
Product and company names are trademarks or trade names of their respective companies.
320104-01 © Copyright 1993, 1994 National Instruments Corporation. All rights reserved. October 1993

What Your Kit Should Contain
The CB-50 I/O connector block kit is available in three versions, depending on your
requirements:
• CB-50 with 0.5 m cable assembly
• CB-50 with 1 m cable assembly
• CB-50 without cable assembly
In addition, each version of the kit contains the following components:
• Interface assembly
- Connector block, ejector ears, and flush-mount and rack-mount brackets
• Screwdriver
• CB-50 I/O Connector Block Installation Guide
If your kit is missing any of the components or if you received the wrong version, contact
National Instruments.
Installation
Warning: Although the connectors are keyed, it is possible to force the connectors into the
header the wrong way. You must be absolutely certain that the connectors are
properly aligned. Failure to do so could cause signals to be connected to the
wrong pins, which could damage the data acquisition board and the computer.
N
ATIONAL INSTRUMENTS IS NOT LIABLE FOR DAMAGE RESULTING FROM SUCH
CONNECTIONS.
1. Plug either end of the ribbon cable into the 50-pin rear panel connector on the board. Align
the tabs and arrows as shown in Figure 1.
2

Align Arrows
Component Side
of Board
Align Keying Tab
Figure 1. Connecting the 50-Pin Connector to Your Data Acquisition Board
2. Firmly push in the connector for proper contact.
3. Insert the ejector ears into the connector block as shown in Figure 2.
Ejector Ears
Connector
2 4 6 8 101214 16
1 3 5 7 9
1 1
18 20 222426
13 15 17
28 303234 36
19 21 232527
29 313335 37
38 40
42 444648 50
39 41
43 45
49
47
Figure 2. Inserting the Ejector Ears into the Connector Block
3

4. If you plan to mount your connector block for stability, choose one of the following
procedures for mounting. If you do not want to mount your connector blocks, proceed to
step 5.
• For flush mounting, insert the flush-mount brackets into the connector block base as
shown in Figure 3.
Flush-Mount Bracket
Figure 3. Inserting the Flush-Mount Brackets
Place the connector block where you want to mount it and screw it into place.
• For rail mounting, pry off the right and left ends of the connector block with a
screwdriver as shown in Figure 4.
Figure 4. Removing the Connector Block Ends
Insert the rail-mount bracket into the slots on the bottom of the connector block as
shown in Figure 5.
4

Rail-Mount Bracket
Figure 5. Inserting the Rail-Mount Bracket
Replace the end of the connector block and push very firmly until it snaps into place.
Repeat for the other side, making sure that both rail-mount brackets are facing the
same direction.
Slide the rail-mount brackets of the connector block onto your rails.
5. Plug the free end of the ribbon cable into the connector block. Align the tabs and arrows as
shown in Figure 6.
Align Arrows Align Keying Tabs
2 4 6 8 101214 16
1 3 5 7 9
1 1
18 20 222426
13 15 17
28 303234 36
19 21 232527
29 313335 37
38 40
42 444648 50
39 41
43 45
49
47
Figure 6. Cable Connections to the CB-50
5

6. Firmly push in the connector until the ejector ears on the block header connector snap into
position.
The numbers on the connector block correspond to the pin numbers of the rear panel I/O
connector on the board.
Removal
1. Press down on the ejector ears of the connector block. The connector will pop out.
2. At the other end, grasp the ribbon cable near the connector end and pull it away from the
board with a rocking motion.
6