Rockwell Automation 1771-PD PID MODULE (+DU) - Manual (Page 69)

Programming
Chapter 3
3Ć26
set point in word W06(W13)
minimum scaling value in word W31(W51)
maximum scaling value in word W32(W52)
loop error in word W62(W69)
read process variable in word W65(W72)
When this bit is reset to 0, the above values are multiplied x1. When
set to 1, the values in words W31(W51) and W32(W52) are
multiplied x10. The other words are multiplied x 10 only if the
values are scaled.
NOTE: The multiplier bit B06 must be examined to determine the
correct value of the loop error in word W62(W69) or the read
process variable in word W65(W72) when either word is read by the
PC processor.
W19(W38)B05, B04 Proportional Gain Multiplier. These two bits
select the multiplier for the integral gain K
I
in word W24(W44)(table
3.F).
W19(W39) B03, B02 Integral Gain Multiplier. These two bits
select the multiplier for the integral gain K
I
in word W24(W44)
(Table 3.F).
Table 3.F
Multiplier Codes
K
P
W19(W39)
K
I
W19(W39)
K
D
W19(W39)
K
F
W30(W50)
B05
B03
B01
B07
B04
B02
B00
B06 Multiplier
0
0
1
1
0
1
0
1
X1
/10
x10
x100
W19(W39)B01, B00 Derivative Gain Multiplier. These two bits
select the multiplier for the derivative gain K
D
in word
W25(W45)(Table 3.F).
W20(W40)Input Filter Time Constant, TA. This word contains the
time constant for the input digital filter. The digital filter is the equivalent
of a single pole low pass filter. Data format is 4-digit BCD (99.99) with