Specifications

Control Block Description ADDvantage-32 PLUS
4-94
If REF is increasing faster than UP, the RMP bit is set high and RP OUT ramps at the UP
value (time period t
1
to t
2
of Figure 4-61). If REF decreases faster than DWN, the RMP
bit is set high and RP OUT ramps at the DWN value (time period t
3
to t
4
of Figure 4-61).
If neither of the preceding conditions is true, the RMP bit is set low and RP OUT equals
REF.
RATE OF CHANGE LIMIT BLOCK
1. Inputs
INP: Analog (Internally connected to the Ramp Output)
RND: Analog
2. Outputs
OUT: Analog
3. Implementation
The rate of change limit block (ROC filter) is internal to the RMP2 Control Block. The
purpose of this stage of the RMP2 block is to round the corners created by the ramp
change block (Figure 4-61B). The ROC filter produces rounding by limiting the ramp
rate of the input to the output over time. The limiting occurs as a result of a calculated
value internal to the RMP2 called the Maximum Rate of Change. When the input is
greater than the Maximum Rate of Change value, the output equals the Maximum Rate of
Change value. When the Maximum Rate of Change equals the rate of the input, the ROC
stops limiting the output.