
65
1
Run Autotune AT:
with cooling
disabled (Function .19 Option 0). Set
Function .4
normal operating temp. Accept AT
Option 15
proportional cycle time
5.8.3 Setting Up Routine for Heat-Cool Control
Temperature
setpoint
e.g. 50% cool
no offset
e.g. 30% heat
Time
Cool
prop band
(offset without
cool strategy
integral action)
consistent
deadband/
overlap
exothermic
change in
load causes
integral to
move prop
bands down
Integral
causes prop
bands to
move
Figure 5-9. Cool Strategy
1. Integral causes linked prop bands to move up.
2. Stabilizes eg. 30% heat.
3. Exothermic load change causes integral to move prop bands
down minimizing and disturbance.
4. Minimum offset achieved (4a = offset without cool strategy
integral action).
5. Stabilizes eg. 50% cool.
6. Consistent dead band/overlap throughout.
STEP ACTION
PARAMETER
NOTE
SP1 cycle time must be compatible with switching
devices used (SP2 cool output is OFF)
Summary of Contents for C9000A SERIES
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