Instruction manual

Timers
890USE18300 September 2003 117
Physical Output The output from a delay-to-stop timer block is a Boolean 1 or 0.
If the output is not inverted, the output will go to 0 when the block has reached its
specified terminal count and it will stay at 0 as long as the timer accumulator holds
the terminal count. The output is 1 when the block looses the terminal count.
If the output is inverted, the output will go to 1 when the block has reached its
specified terminal count and will stay at 1 as long as the timer accumulator holds the
terminal count. The output is 0 when the block looses the terminal count.
The physical output (See Configuring the Physical Output from a Reflex Block,
p. 27) needs to be mapped to an action module:
The action module may be a digital output module on the island bus. In this case,
you need to specify one of the digital output channels as the destination for the
block’s output.
If the timer is the first block in a nested reflex action, the action module needs to
be the same action module as the one specified for the second reflex block.
Specify the channel as None.
When the output from a reflex block is mapped to a channel on a digital output
module, that channel becomes dedicated to the reflex action and can no longer use
data from the fieldbus master to update its field device. The fieldbus master still has
the ability to write data to this bit address in the NIM, and the reflex action editor lets
you use this data from the fieldbus master as an input to the block.
Power-up and
Fallback
Upon power-up, the timer’s output data is reset to the terminal count.
If an error causes the timer block to go to its fallback state, the output freezes in its
last active state. Upon removal of the error condition, the timer is reset to the
terminal count.