Watlow Series 982 - Manual (Page 125)

WATLOW Series 982 User’s Manual 9.11 Software Features, Chapter 9
Software
Sample Application
A Series 982 controls the temperature in an environmental chamber. The
sensor is very sensitive to changes caused by air flow in the chamber. The
turbulence in the chamber makes the controller display jump two to three
degrees. To remove this display dithering set the filter time constant
[Ftr1] for input 1 to two seconds. This will smooth the display and pro-
vide a more realistic reading.
Figure 9.11b -
Humidity cham-
ber with input fil-
tering.
input 1 output 1
limit
limit
sensor
Te mpe ra t ure Cha mbe r
temperature
sensor
heater
TL
TL
W WA
PROCESS
L1 L2 L3 L4
DEV
% OUT DISPLAY
SERIES 982
MODE
HOLD
RUN
time
tem
perat
ure
Display reading with input filter off.
time
tem
perat
ure
Display reading with input filter on.
Figure 9.11a -
Display readings
with input filter-
ing.