Function Blocks
Function Block Reference Guide
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2.55 ROC Function Block
Description
The
ROC
label stands for
Rate of Change
.
This block is part of the Auxiliary category. It looks like this
graphically on the Control Builder.
Function
Provides:
•
an analog output representing units per minute change of the analog input.
•
compare setpoints for high and low rate of change.
•
compare selections for increasing, decreasing or both directions of change.
•
a logic 1(ON) output when input rate exceeds high rate setpoint
•
a logic 1(ON) output when input rate is less than the low rate setpoint.
Inputs
IN = Analog Input
Outputs
HI_RC = ON if input rate exceeds High Rate setpoint
LO_RC = ON if input rate is less than the Low Rate setpoint
RATE = Analog Output representing Engineering Units per minute of change of the Analog Input
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