Using The Communications Toggle Push Button - Allen-Bradley MicroLogix 1200 User Manual

4-2 Communication Connections
Using the
Communications Toggle
Push Button
Connecting to the
RS-232 Port
Publication 1762-UM001B-EN-P
The Communications Toggle Push Button is located on the processor
under the processor door (if installed), as shown below.
Use the Communications Toggle Push Button to change from the
user-defined communication configuration to the default communications
mode and back. The Default Communications (DCOMM) LED operates to
show when the controller is in the default communications mode (settings
shown on page 4-1).
0
1
COM
Communications Toggle
Push Button
The Communication Toggle Push Button must be pressed
NOTE
and held for one second to activate.
There are two ways to connect the MicroLogix 1200 programmable
controller to your personal computer using the DF1 protocol: using a
point-to-point connection, or using a modem. Descriptions of these
methods follow.
All devices connected to the RS-232 channel must be
ATTENTION
referenced to controller ground, or be floating (not
referenced to a potential other than ground). Failure to
!
follow this procedure may result in property damage or
personal injury.
• For 1762-L24BWA and 1762-L40BWA controllers:
The COM of the sensor supply is also connected to
chassis ground internally. The 24V dc sensor power
source should not be used to power output circuits. It
should only be used to power input devices.
• For 1762-L24BXB and 1762-L40BXB controllers:
The VDC NEUT or common terminal of the power
supply is also connected to chassis ground internally.
0
1
COM