Specifications

SP2 - Set point two. Not configured into control and non-
functional. Set to “20.”
AT - Adaptive Tune. Analyzes and inputs optimum PID
values when temperature has reached set point. This
function does not have a value; it is either “ON” or “OFF.”
(See Furnace Operation for function of Adaptive Tune).
ATR - Adaptive Tune Range setting. Determines the op-
erational band width of the adaptive tuning function. Self
Tuning automatically determines this setting.
AL1 - Alarm 1. A full scale alarm which protects load and
furnace when temperature exceeds preset value. Furnace
will control temperature at the preset temperature value; it
will not shut off furnace. Push up or down button to set.
The next three parameters - Proportional (PB) Integral
(+i) and Derivative (+d) - are the three control parameters
of a P.l.D. control system. These parameters will be set
when you tune your furnace. (See Self-Adaptive
Tuning.)
Pb - Proportional.
(+i) - Integral.
(+d) - Derivative.
The next two parameters - cutback low (cbl) and cutback
high (cbh) - are to aid the control in preventing tempera-
ture overshoots and undershoots. The point from set point
where the power starts “cutting back” is defined as the
cutback value. These values are also automatically
adjusted by the Self Tuning and Adaptive Tuning features.
These values cannot be changed by the user; the con-
troller automatically installs optimum cutback values when
in Self Tuning and Adaptive Tuning.
HL - Output Power limits the average maximum power
that is applied to the heating elements. Normal setting is
100%. If you plan to use the furnace below 260°C (500°F)
the output power may be reduced. This will significantly
shorten the time it takes for stabilization. It will also
reduce drastic temperature overshoots. Contact
Barnstead/Thermolyne Customer Service for advice on
the proper value to use. Remember that this parameter
does not reduce the voltage to the elements. It reduces
the average power to the elements by cycling power on
and off.
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MULTI-PROGRAMMABLE MODELS
Note
Barnstead|Thermolyne recommends
that you set the value either at maxi-
mum operating temperature of the fur-
nace (1100°C = 2012°F) or a value of
20° above your working temperature if
you desire to provide protection for
your workload.