15
Ramp Rate
Each step of a firing program must have a programmed Rate of temperature increase or
decrease. These rate values are selected as Degrees per Hour. During the
programming the display prompt for Rate settings are
rA
followed by the step number
like
rA1
,
rA2
,
rA3
, etc… This may be either a positive number (for heating), or a
negative number for cooling. To heat or cool as fast as possible, an alternative setting is
available at the beginning or end of the temperature range. This setting appears as
FULL
on the controller display. If zero is set for any rate, this tells the controller that
there are no more steps to your firing schedule, and ends your program. This feature
can also be used to erase an entire firing program by setting the first
rA1
value to zero.
The ramp rates built in to the controller were selected to give optimum performance for
most projects. You may need to modify this part of the firing schedule if you have a
special project.
Target or Set Point Temperature
After the ramp rate has been set, the target hold temperature is then selected. Once
again, the built in temperatures are suitable for a typical project, by may need to be
modified for certain special projects.
Hold / Soak Time
Hold or soak times are important parts of the firing cycle. The heat soak, or heat hold,
allows both the kiln and glass to completely stabilize before continuing to the specified
high temperature. The cooling soak or hold (also called the pre-annealing soak),
commonly at about 975
o
F to 1000
o
F degrees allows stress built up in the cooling glass to
be released slowly. Without the cooling soak, the glass could retain stress resulting in
breaks.
