EZ Automation EZTouch I/O Flex, Instruction Manual

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EZTouchPLC
57 / 64
Maintenance and Troubleshooting
Hardware Maintenance
Routine maintenance checks should be performed on the unit to avoid any risk of
hardware problems. The
EZTouchPLC
is designed to be a very rugged controller so
that just a few checks periodically will help keep it up and running.
The key points to be checked include:
· Ambient operating conditions
· Wiring and connections
Maintaining the Ambient Operating Conditions
Keeping the
EZTouchPLC
unit's environment within specified operating
conditions is the best method to minimize the maintenance.
1.
Always ensure that ambient temperature inside the cabinet is within
EZTouchPLC
unit's temperature ratings.
2.
If any other equipment inside or outside of the cabinet is producing heat,
employ cooling methods like a blower fan to reduce 'hot spots' around the
EZTouchPLC
.
3.
Periodically inspect and clean if there are any air filters on the cabinet. Ensure
that the unit is free from dust, humidity and corrosive gases.
Error Checking Process
The
EZTouchPLC
performs a standard diagnostic routine during each CPU scan.
This is called the error-checking step. The primary task of this step is to
identify various types of CPU and I/O failures. We classify these errors/failures
broadly into two categories: Fatal and Non-Fatal.
Fatal Errors
These errors are the ones that lead to the system failure. During the CPU scan
if a fatal error is detected, PLC is automatically switched out of Run mode and
allI/O points are disabled. Some instances of fatal errors include: Wrong
parity value, Programming errors, etc. The
EZTouchPLC
will not go into Run
Mode from Program if it detects a fatal error.
Non-Fatal Errors
These errors just need your attention and are not detrimental to PLC
operation.Unlike fatal errors, the PLC will continue in Run mode despite an
occurrence of non-fatal errors. When you identify such errors, you can
proceed with an orderly shutdown and take the required corrective action.
An example of non-fatal error is – a minor programming error.