Allen-Bradley 1772-LH

The main program follows the data table in memory and stores all the user program instructions that make up the ladder diagram program. Most instructions are stored in one memory word. Some advanced instructions require up to 8 memory words. Unless specified elsewhere, instructions require one word of user memory when the address is 3778 or below and two words of user memory when the address is 4008 or above. Your program is a group of ladder diagram instructions used to control an application. It is initially entered into memory using an industrial terminal.

In the processor, the inhibit feature is active when the user removes a jumper from the 1772-LH interface module. This prohibits alteration of the user program in any processor mode. The alteration of data table words 4008 and above is also prohibited except through the user program. Only data table values between word addresses 0108 and 3778 can be changed either in run/prog or prog modes.

The installer and programmer of the PLC-2/30 Programmable Controller should work together to determine the best placement of the I/O modules within the I/O chassis. To simplify installation and troubleshooting procedures, it may be desirable to group like modules together. The PLC-2/30 processor's functions include:
- Relay-type functions (Examine On, Examine Off, Output Energize, Output Latch, Output Unlatch and Branching)
-Complete forced I/O
-Data transfer
-Data comparison
-Three-digit, four-function arithmetic (+, -, , :-) :-:-
-Timing functions: On-Delay and Off-Delay, Retentive and Nonretentive with time bases of 1.0, 0.1 and 0.01 seconds (timing range 0.02 to 999 seconds).
-Bidirectional counting (up or down) with a range of 0 to 999 counts.
-Self-monitoring/diagnostic capabilities
-Expandable data table
-Memory capacity of 16,256 words
-896 I/O device capacity is available in local or remote configurations.
-896 inputs and 896 outputs when used with specific configurations.