Bradley Smoker PLC-5 Effect of Inserting Ladder Rungs at 56K-word Limit, No impact 50 ms/Kwords

Maximizing System Performance C-13

Effect of Inserting

Ladder Rungs at the

56K-word Limit

This consideration applies to PLC-5/60, -5/60L, -5/80, and -5/80E controllers when you are editing a program file that approaches the maximum file limit of 57,344 words.

The amount of time that the messaging and block-transfers can be delayed is proportional to the size (K words) of the ladder file. The following table lists the performance effects (when using any of the 6200 Series PLC-5 Programming Software releases that support the controller you are using).

Effected Data	Online Operations via any DH+ Channel:
Transfers
	Perform a Page Up/Page	Insert/Delete Ladder
	Down at the End of a	Rungs
	Program File
Remote block-transfers	20 ms/K words	50 ms/Kwords
DH+ messages	20 ms/K words	50 ms/Kwords
Serial port messages	200 ms/K words	50 ms/Kwords
Channel 3A messages	no impact	50 ms/Kwords

You should re-design your programs to avoid possible communication pauses if you currently:

•use large ladder logic program files

•have time critical remote block-transfers and/or serial, DH+, and channel 3A messages

•must edit the program online during run mode

For best controller performance, segment your program files by using modular programming design practices, such as main control programs (MCPs), sequential function charts (SFCs), and the jump to subroutine (JSR) instruction.

Performing run-time or program-mode editing of ladder files that approach the maximum program file size of 57,344 words could:

•prevent the rung from being inserted

•cause suspension of the operation by 6200 Series PLC-5 Programming Software (release 4.3 and later)

To avoid or correct this problem, segment your program file using modular programming, such as main control programs (MCPs), sequential function charts (SFCs), and the jump to subroutine (JSR) instruction.

If you cannot segment your program file, save the file often while editing it.

If you encounter the error Memory Unavailable for Attempted Operation, then clear controller memory.

Publication 1785-UM012D-EN-P - July 2005