Function Blocks
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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Function Block Reference Guide
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