Honeywell X Series User Manual page 304

Because of this small, but increasing contribution to F
that in this trace the temperature exceeds 121.11ºC, the F
minutes, at which point the sterilisation is complete, and cooling begins.
For some applications it is allowed to report the F
the sample cools back to the start temperature, in this example 100 ºC, and so the
contribution under the curve up to t = 22 minutes would be included in the reported
F
20 minutes, and the extra 1.1 having accumulated during the cooling back to 100 ºC
between t = 20 minutes and t = 22 minutes.
The terms used in setting up the F
rised in this table.
Term
F
0
z factor
Start
temperature
Reference
Temperature
Include
cooling phase
Completion
Value
For setting up the Fo calculation refer to the
298
. The final F value might then be 16.1, say, with 15 having been achieved up to t =
0 0
The equivalent time in minutes at 121.11ºC that would pro-
duce the same degree of sterilisation. This is the totaliser out-
put value
The temperature increase in ºC above the reference tempera-
ture that will produce a 10-fold increase in the rate of sterilisa-
tion
The temperature in ºC above which the contributions to F0
can be counted
The reference temperature for sterilisation, normally
ºC, can be altered if required.
121.11
If TRUE, contributions to F
value has been reached and while the temperature is still
above the start temperature. If FALSE, these contributions are
not included
F totaliser value can be set if "Include
The maximum
0
cooling phase" is not selected, the totaliser will stop at
this value of F .
0
0
totaliser, together with their default values, are summa-
0
Definition
can be included after the target
0
"Totaliser Menu" on page 70.
once T reaches 100 ºC, and the fact
value reaches 15 at time t = 20
0
value that is finally achieved as
0
Default
values
10
100
ºC
121.11
FALSE
15
43-TV-25-30 Iss.6 GLO Aug 07 UK
Allowed
Range
5 - 20
90 - 120
-
1 - 999