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PROCESS VARIABLE COMPARISON
– This allows
the comparison of current Position, Velocity, Torque or analog
input to a pre-defined register value, with either a “>”,“<” or
“<window<” result resulting in a “logic-true” condition. If the
window option is selected, the window value for the comparison
will need to be entered.
Note: These are all Actual values, rather than Commanded values.
Figure 12.27 - Register Comparison Screen
OPEN (NULL) CONNECTION
- This simply inserts
an open circuit (always false) at the current rung location. This
cannot be used as the only input location on a given rung, but
rather must be used in conjunction with other logic conditions.
OUTPUT OPERATIONS
OUTPUT COIL
- This is a standard ladder logic
output coil. It will go true (“on”) whenever the conditions in the
rung are met to result in a true condition.
LATCH OUTPUT COIL
- When the rung conditions are
true at this coil, it latches the associated output (turns on and stays
on) until it is unlatched with the Unlatch Output Coil operation.
1 2 : P R O G R A M M I N G
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