ALLEN BRADLEY 1747-L551 PLC Processor

7–10
Wiring Your I/O Modules
Using the Removable
Terminal Block (RTB)
The Removable Terminal Block (RTB) is provided on all 12-point
and 16-point discrete I/O modules and analog modules. They allow
for faster and more convenient wiring of the I/O modules. The
modules and the RTB are color-coded as follows:
Color
Type of I/O Removable Terminal Block
Red
AC inputs/outputs
Blue
DC inputs/outputs
Orange
relay outputs
Green
specialty modules
Replacement terminal blocks are available if they are lost or
damaged. See the replacement part list in chapter 11.
Removing the RTB
Below are guidelines for removing the I/O Removable Terminal
Block.
!
ATTENTION: Never install or remove I/O modules
or terminal blocks while the SLC is powered.
1. If the I/O module is already installed in the chassis, remove
power to the SLC.
2. Unscrew the upper right and lower left terminal block release
screws.
3. Grasp the RTB with your thumb and forefinger and pull straight
out.
4. Label the RTB with appropriate slot, rack (chassis) and module
identification.
Terminal Block Release
Screw
Dot indicates terminal
number 0
(or top of I/O wiring).
SLOT______RACK_____
_
• MODULE______
Terminal Block
Release Screw
Publication 1747-6.2