Instruction manual

3332
Calculate and enter these
numbers:
Rate [rAtE] = T/8
Reset [rSEt] = rate x 4
Gain [Gn.01] = Step (15) x 0.6
Tu n i n g
P ro c e d u re s
If overcooling exists on
heat/cool processes
after autotuning,
decrease Gain Ratio
[ Gr.o2 ] in steps of 0.1
until oscillation is
minimal. If cooling is
sluggish, increase the
value in steps of 0.1
until optimum results
are achieved.
Gain ratio [ Gr.o2 ] is
the cooling gain
expressed as a factor
of the heating gain.
Ex. [ Gn.01 ] = 100
[ Gr.o2 ] = .5
Cooling Gain = 50
Tu n i n g
P ro c e d u re s
Manual Tuning Procedure - Temperature
Controller (Zeigler-Nichols PID Method)
This tuning method may be used if the spread between ambi-
ent temperature and process operating temperature is small.
For best results, the use of a recording device is suggested
when tuning with this method.
1) Disable any cooling device used.
2) Apply power and place the controller in Standby by
pressing and holding the Mode key for four sec-
onds.
3) Access menu level “02” following instructions given
previously.
4) Using Raise or Lower key, adjust setpoint to
desired value.
5) Using the Parameter/Access key, index to Heat Gain
[ Gn.o1 ]. Select [ 01 ].
6) Index to Gain Ratio [ Gr.o2 ] and select [ 1.0 ].
7) Index to Rate [ rAtE ] and select [ 00 ].
8) Index to Reset [ rSEt ] and select [ 00 ]. Note: In order to
set Reset to [ 00 ] , Rate must first be set to [ 00 ].
9) Change to menu level “03”.
10) Index to Cycle Time 1 [ CY.t1 ] and select the timebase,
in seconds, appropriate to the device being controlled.
(See note on page 27.)