Specifications

Control Block Description ADDvantage-32 PLUS
4-96
Exact Time ROC Filter (Slope) at OUT
1 Sec. 5 FPM/SEC
2 Sec. 10 FPM/SEC
3 Sec. 15 FPM/SEC
4 Sec. 20 FPM/SEC
5 Sec. 20 FPM/SEC
Notice that since the input to the filter is 20.0 FPM/SEC, the rate from 4 to 5 Sec. of the
output does not increase past 20 FPM/SEC.
At 5 seconds, the Rate Change block reaches its final value (100 FPM) and the rate of
change becomes zero. The filter will now cause the output rate to decrease by
5 FPM/SEC
2
from its maximum value of 20FPM/S while the input rate is zero, thus:
Exact Time Maximum rate of change (Slope)
1 Sec. 5 FPM/SEC
2 Sec. 10 FPM/SEC
3 Sec. 15 FPM/SEC
4 Sec. 20 FPM/SEC
5 Sec. 20 FPM/SEC
6 Sec. 15 FPM/SEC
7 Sec. 10 FPM/SEC
8 Sec. 5 FPM/SEC
9 Sec. 0 FPM/SEC
10 Sec. 0 FPM/SEC
To accurately select an appropriate value for the RND input, apply Equation 4-61.1 in the
form:
S = Rate/T
Where:
S = Value of Analog input RND
Rate = Value of UP or DWN.
T = Desired time length for ROC to provide rounding
Equation 4-61.2