WATLOW Series 965 User's Manual
19
Setup, Chapter 4
Operation
M
75
Pb1
rE1/It1
rA1/dE1
Ct1
ALO
AHI
CAL
AUt
( )
( )
( )
( )
( )
( )
( )
( )
Pb2
( )
rE2/It2
rA2/dE2
Ct2
( )
( )
( )
Proportional band 1
Reset 1/Integral
Cycle time 1
Proportional band 2
Reset 1/Integral 1
Rate 2/Deviative 2
Cycle time 2
Rate 1/Deviative 1
Control Set Point
Alarm low
Alarm high
Calibration offset
Auto-tune
= Prompt appears or not according
to control configuration.
Operation Parameters
Set Point: Sets the operating set point for Output 1. Represents the process
value the system tries to achieve for Output 1. "SP" does not appear, the con-
trol set point value will. The lower display may be blank if dSP = Pro. If in a
ramping mode, the lower display alternately flashes the desired end set point
and rP.
Proportional Band 1 & 2 : A proportional band expressed in degrees or % of
span, within which a proportioning function is active for Output 1 or 2. When
Pb1 = 0, the unit functions as an on/off control on Output 1 and 2. Pb2 will not
appear if Pb1 = 0 or Ot2
≠
Con. The switching differential is determined by the
HSC parameter.
If dFL = US: Range Pb1: 0 to 999
°
F/0 to 555
°
C/0 to 999 Units; 0.0 to 9.9
°
F/
0.0 to 5.5
°
C/0.0 to 9.9 units, Pb2: The same as Pb1 except lower limit is 1.
Defaults:
Pb1 = 25
°
F/2.5
°
F
Pb2 = 25
If dFL = SI: Range: 0 to 999.9% of span Defaults:
Pb1 = 3.0% Pb2 = 3.0%
Reset /Integral 1 & 2: An integral control action for Output 1 or 2 that auto-
matically eliminates offset, or "droop," between set point and actual process
temperature. rE1/It1: Will not appear if Pb1 = 0. rE2/It2: Appears if Pb1
≠
0
and Ot2 = Con. Either reset (rE) or integral (It) will appear depending on how
the dFL parameter is set in the Calibration menu. See Appendix II.
If dFL = US: Range: 0 to 9.99 repeats/minute Default: 0.00
If dFL = SI: Range: 00.1 to 9.99 minutes per repeat
Default: 0.00
Rate /Derivative 1 & 2 : The rate (derivative) function for Output 1 or Output
2. Eliminate over shoot on start up, or after the set point changes. rA1/dE1:
Will not appear if Pb1 = 0. rA2/dE2: Appears if Pb1
≠
0 and Ot2 = Con.
Either rate (rA) or derivative (dE) appears depending on how dFL is set in the
Calibration menu. If dFL = US or SI: Range: 0 to 9.99 minutes Default: 0.00
[
SP ]
Figure 24 -
The Operation Menu.
NOTE:
The upper display
will always return to
the process value
after 1 minute
without key strokes.
rE1/It1
rE2/It2
Cycle Time 1 & 2: Time for a controller to complete one time proportioned
cycle for Output 1 or Output 2; expressed in seconds. Ct1: Will not appear if
Pb1 = 0, or Output 1 is 4-20mA. Ct2: Will not appear if Pb1 = 0 or Ot2
≠
Con.
If a mechanical relay or contactor is switching power to the load, a longer
cycle time may be desirable to minimize wear on the mechanical compo-
nents. Typical life of a mechanical relay is 100,000 cycles.
Range: 0.1 to 999.9
Default: 5.0
Ct1
Ct2
rA1/dE1
rA2/dE2
Pb1
Pb2
