FPC-8057 User’s Manual
Programming Considerations To conform to ICS Safety Recommendations, checks should be placed i n the
controller to ensure that all writable registers that control critical parts of
plant or machinery have limit checks built into the program, with an out-of-
limit safe shut down procedure to ensure safety of personnel.
ICS 3-304.81 Safety Recommendations: Consideration should be given to the use of an emergency stop
function, which is independent of the programmable contro ller.
Where the operator is exposed to the machinery, such as in loading or
unloading a machine tool, or where the machine cycles automatically,
consideration should be given to the use of an electromechanical override
or other redundant means, independent of the p rogrammab le contr oller, fo r
starting and interrupting the cycle.
If provision is required for changing programs while the equipment is in
operation, consideration should be given to the use of locks or other
means of assuring that only authorized personnel can make such
changes.
These recommendations are intended as safeguards against the failure of
critical components and the effects of such failures or the inadvertent
errors that might be introduced if programs are changed while the
equipment is in operation. *
z The ICS 3-304.81 Safety Recommendations are reproduced by
permission of the National Electrical Manufacturers Associat ion from
NEMA ICS 3-304
Installation Instructions 13