Allen Bradley PLC SLC500 Level 1

Software: RSLogix 500
PLC-Type: Allen Bradley SLC500 PLC

Course Documentation

• Training Log
• Pre Course Exercises
• Course Exercises
• Post Course Exercises
• Filofax Pocket Reference Guides

Course Content
To fault find a system you need to know EXACTLY how it works

HOW EXACTLY DOES A PLC WORK?

• Am I getting the input to the PLC?
• The Led on the output card means i am getting voltage out right? does it?
• What exactly happens in between? ,theres more than just a program in the CPU
• How exactly does it scan the program?
• What is this Watchdog Timer? Is it that important?
• Can I use the same output twice? That's bad programming isn't it?
• A PLC is a logic controller, so use a logical approach to fault find it.
• What are the 8 simple test points to check?
• The PLC is in RUN, that means theres a program right? does it?
• FORCING a bit and toggling a bit is pretty much the same yeah? depends on which PLC

Then you need to Know the specifics

HOW DO I DO THE FOLLOWING?
(some straight forward some not so)

• Check power is ON and PLC is in right mode (RUN or Program)
• Check LEDs for fault definition
• Check and Change Modules if required (with spares and without spares)
• System connection
• Establish link to PLC (RSLinx, a major problem area these days)
• Create a blank project and take a backup (just in case I mess up)
• Open the correct project Off Line and link to PLC
• Interrogate errors in Status table
• Identify if it is a hardware or software fault?
• Identify if it is a PLC or Comms fault
• Change the battery
• Check all settings against a template, Node Address etc.
• Check Hardware Configuration
• Clear Memory and Download program
• Check software against latest copy (Compare function)
• Monitor program
• Searching for specific operands and instructions
• Changing timer, counter values On Line
• Making minor mods Off Line and On line
• Check or create a Custom Monitor table to establish parameter status
• Create a Histogram to monitor address transitions
• Creat a Trend to trend address status or values
• Altering timer, counter and other data table values if required
• Force a parameter if required
• Toggling addresses to move program on in sequence
• Call up documentation to assist with software diagnostics
• Printing Cross Reference / Program Listings etc.

Background information also covered

Understanding of the following:

• Number formats, bits,words,
• Binary, floating point, integer
• Program blocks and Data Tables, B3, T4, N7 etc
• How to monitor various blocks
• Understand basic Ladder programs
• Basic Instructions, contacts, Set, reset etc.
• Timers, Counters
• Comparators, Maths
• Altering values in a data table
• Toggling v Forcing
• Back tracking through a program to establish where power flow stops
• Overall reset procedure
• Fault finding tips

Course Equipment Per Delegate

• SLC500 PLC
• PC or Laptop
• Simulator