Rockwell Automation 1771-DB BASIC MODULE - Manual (Page 35)

Chapter
Installing the BASIC Module 1
1 -11
Use the plastic keying clips shipped with each I/O chassis to key the I/O
slot to accept only a BASIC module.
The BASIC module is slotted in two places on the rear edge of the circuit
board. The position of the keys on the backplane connector must
correspond to these slots to allow insertion of the module.
Snap the keys onto the upper backplane connectors between 8 and 10 and
between 32 and 34. (Same as Series A)
I/O chassis
Keying Clips
ATTENTION: Insert or remove
keying bands with your fingers.
Keying Positions
Between 8 and 10
Between 32 and 34
20315
Upper
Connector
You can change the position of these keys if subsequent system design and
rewiring makes insertion of a different type of module necessary.
ATTENTION: Observe these precautions when
inserting or removing keying clips:
Insert or remove keying clips with your fingers.
Make sure that keying placement is correct.
Incorrect keying or the use of a tool can result in damage to the
backplane connector and possible system faults.
Key the Backplane Connector