ELECTRONIC PERSONAL DOSEMETER HANDBOOK
EPD/HB/40521/000
OPERATING INSTRUCTIONS
ISSUE 5
Thermo
Page
13
SECTION 3
OPERATING INSTRUCTIONS
This section explains the essential functions performed by the EPD and describes
operating instructions that will allow the user to display data, acknowledge alarms
and operate the EPD.
3.1
LCD Display and Backlight
A custom-designed LCD display on the top of the EPD provides a visual interface
for viewing dose and other EPD data. The EPD display is illustrated in Figure 3.2,
which shows all segments in the on state. All segments are activated in this way
temporarily during the start-up sequence, and during user initiated
Confidence
Test
, (see Section 3.5.7). On completion of the start-up sequence or
Confidence
Test
the default display will appear.
The default display is preset at the factory to show Hp(10) (the penetrating or
deep dose), or another default display as specified by the customer. The default
display can also be changed by the customer after delivery, to any display shown
in Figure 3.4. Default settings and other display controls are changed using a
suitable IR communications link and software (e.g.
EasyEPD2
). For example, the
display can be configured to display values in either Sieverts or rems.
The EPD is provided with many different displays in order to provide a powerful
‘stand-alone’ facility for users not having direct access to communications
software such as
EasyEPD2
. However for many users the sheer number of
displays available may lead to confusion and Thermo has therefore provided a
facility for unwanted or unnecessary displays to be disabled.
Backlight Operation
The EPD is equipped with a display backlight to enable the display to be read in
the dark. The following points should be noted:
♦
The backlight will only function if it is enabled over the IR communications
link.
♦
The backlight only operates for a short period after the button is pressed.
This is to conserve battery life.
♦
When the backlight is enabled but currently off, the first short press of the
button serves only to activate the backlight and does not cause a change of
display selection. This may cause confusion in bright day-time conditions
when the backlight effect is not apparent and the user may assume that a
button press operation has somehow been ‘lost’.
