Fluke Biomedical TNT 12000 - Manual (Page 63)

Operation
How to Use the Dosimeter Detector (TNT 12000 DoseMate)
2
2-35
External Temperature/Pressure Compensation Mode
It is assumed that air density correction is set to On in the steps that follow.
1. Use C, D, A, and B to highlight the checkbox next to the User Set Temperature
label and push E to toggle the checkbox. When the box is checked, the button
to the right of the checkbox is enabled. When this checkbox is not checked, internal
temperature compensation is activated.
2. Use B to highlight the temperature button and push E to change the temperature
value. The NUMERIC screen shows in the Display.
3. Use C, D, A, and B to highlight a number and push E to add the number to the
entry.
4. When the temperature value is set, highlight the Save button and push E to set
the temperature compensation value.
5. Use C, D, A, and B to highlight the checkbox next to the User Set Pressure label
and push E to toggle the checkbox. When the box is checked, the button to the
right of the checkbox is enabled. When this checkbox is not checked, internal
pressure compensation is activated.
6. Use C, D, A, and B to highlight the Reference Temperature dropdown box and push
E .
7. Use C or D to highlight 20 or 22 and push E. The ion chamber is calibrated at
this reference temperature. See the Ion Chamber Specifications for the highlighted
chamber in Appendix A, B, C, or D.
8. Use C or D to highlight the Continue button and push E. The mode is set
and the MEASUREMENT screen shows in the Display.
Internal Temperature/Pressure Compensation Mode
When the Dosimeter is set for internal temperature compensation, the temperature value
is set by an internal sensor. This temperature can be different than the temperature of the
ion chamber connected to the Detector. The Detector and the ion chamber must be the
same temperature as the environment before a measurement.
The Dosimeter internal temperature approximately 30 minutes after it is turned on is
typically 10 to 15 ° C above ambient temperature. At standard conditions of 22 ° C and
760 mm Hg , a change of 1 ° C ~ 0.36 % change in ADC. Fluke Biomedical recommends
the internal temperature sensor only be used to measure temperature after the Detector is
turned on and the Dosimeter and ion chamber are the same temperature as the
environment. Then set this temperature into the Detector manually.
Note
With its internal temperature compensation, the internal pressure sensor
works in all conditions.