Rockwell Automation 1772-LP3 PLC - 2/30 Programmable Controller Programming and Operations Manual - Manual (Page 17)

2
Chapter
2Ć1
Hardware Considerations
This chapter describes only those hardware items required when
programming or operating the PLC-2/30 programmable controller. For
more complete hardware information, refer to the PLC-2/20, PLC-2/30
Programmable Controller Assembly and Installation Manual (publication
no. 1772-6.6.2).
A four-position mode select switch (Figure 2.1) is located on the front of
the processor. You can select one of four positions with this switch:
PROG — This switch position places the processor in the program
mode. It is used when instructions are entered into memory. They can be
entered from an industrial terminal, a 1770-SA digital cassette recorder
or a 1770-SB data cartridge recorder. All outputs are disabled when the
switch is in this position.
TEST — This switch position places the processor in the test mode. The
user program is tested under simulated operating conditions without
actually energizing any output devices. All outputs are disabled in this
switch position.
RUN — This switch position places the processor in the run mode.
The user program will be executed and outputs are controlled by the
program. Changes to the user program or data table are not permitted in
this switch position.
RUN/PROG — This switch position places the processor in the
run/program mode. The processor functions as it does in the RUN
position. In this position, you can cause the processor to go into the
program or test mode without having to turn the switch to that position.
On-line changes to the program and/or data table are allowed in this
position with 1770-T3 or 1784-T50 industrial terminals.
The key can be removed from the processor in any of the four switch
positions.
2.0
General
2.1
Mode Select Switch