Rockwell Automation 1769-HSC Compact High Speed Counter Module - Manual (Page 42)

42 Rockwell Automation Publication 1769-UM006E-EN-P - July 2013
Chapter 2 Module Operation
Fault State Run (FSR)
Similar to Program State Run, Fault State Run lets you specify, on a bit basis, that
the output should continue to be controlled by the module as if it were Run state.
That is, events on the module or changes in the output image will affect the
physical outputs without regard to the Fault_HLS or UDSS state indicated.
When this bit is set, the corresponding Fault mode and fault value bits are
ignored.
FSR sets the module according to the value configured for Output Fault State
Run, as described on
page 77 .
ATTENTION: Selecting this option lets outputs change state while
ladder logic is not running. You must take care to assure that this
does not pose a risk of injury or equipment damage when selecting
this option.
IMPORTANT The prescan initiated by some controllers can have an effect on the
outputs. To overcome any changes in physical output states caused by
this, use retentive output instructions (for example, latch or unlatch)
when bit manipulations are done on the Output image of this module
in ladder logic.
This applies to a wide range of bits when Fault State Run is selected,
because presetting a counter, enabling a range, changing a mask, and
changing configuration array settings can cause ranges and outputs to
change state.