GE Series 90-30 PLC

13-8 Series 90-30 PLC Installation and Hardware Manual – August 2002 GFK-0356Q
13
Preventive Maintenance Suggestions
Series 90-30 PLC Preventive Maintenance
Item
No.
Description Recommendation
1 Safety ground and
electrical system
Check frequently to ensure that safety ground connections are secure and
that electrical cables and conduits are secure and in good condition.
2 CPU Memory backup
battery
Replace annually or as appropriate for your application.* Check Chapter
5 for instructions on how to avoid loss of memory contents when
replacing battery.
3 Option Module
backup battery
Replace annually. Check user’s manual for additional instructions.
Check Chapter 5 for instructions on how to avoid loss of memory
contents when replacing battery.
4 Ventilation If using ventilation fan in enclosure, check for proper operation. Keep
fingers and tools away from moving fans. Clean or replace ventilation
air filter, if using one, at least monthly.
5 Mechanical tightness With power OFF, check that connectors and modules are seated securely
in their sockets and that wire connections are secure. For low vibration
installations, perform annually. For high vibration installations, check at
least quarterly.
6 Enclosure Check annually. With power OFF, remove manuals, prints, or other
loose material that could cause shorts or ventilation blockage, or that are
flammable, from inside of enclosure. Gently vacuum dust and dirt that
has collected on components. Use vacuum cleaner, not compressed air,
for this task.
7 Program backup Do this initially after creating any application programs, such as the
ladder logic program, motion programs, etc. Then, any time a change is
made to a program, make at least one (several is better) new backup
copy. Keep old copies (clearly marked) for a reasonable period of time
in case you need to go back to the old design.
Document each backup copy as to what equipment it is for, date it was
created or modified, version number (if any), and author’s name.
Keep master backup copies in a safe place. Make working copies
available to those responsible for maintaining the equipment.
*See “Factors Affecting Battery Life” in Chapter 5.