ENMET PGD2 - Manual (Page 16)

ENMET Corporation PGD2
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6.17 Sensor Zero
Note: From software version 1.20 this facility can be disabled via the PC configuration program and may therefore be unavailable on
certain instruments.
The sensors can be automatically zeroed without the need for a complete re-calibration of the instrument. This is performed using the
sensor zero function. This function can only be accessed during the first minute of the instrument being switched on.
WARNING: This must only be carried out by authorized personnel in a fresh air environment, i.e. where it is known that there
are no toxic (e.g. fumes from vehicles) or flammable gases present.
Slight variations in the zero readings may occur if the instrument is moved between environments of significantly different
temperature. (Also refer to Section 12.3.4. for instruments containing Oxygen Sensors).
To carry out the zeroing function (during the first minute of the instrument being switched on) select the PGD Serial No. via the menu
button (Section 6.5) and press the right arrow key.
The instrument will show: -
This process takes approximately 30 seconds to complete. The instrument then returns to the normal display with the toxic and
flammable sensor readings set at zero and the oxygen reading set at
20.9%.
6.18 EXP / LEL / VOL Display options
The display format for the flammable sensor can be configured to read in either of the following modes:-
EXP or LEL both of these modes display the flammable sensor
reading as a % of the Lower Explosive Limit (LEL) for
the gas being measured.
VOL this mode displays the flammable sensor reading as a
concentration of the gas being measured in % volume.
For example, Methane gas is explosive with air in concentrations between approximately 5% and 15%. The Lower Explosive Limit
(LEL) is therefore 5% by volume.
The following table gives examples of how various Methane gas concentrations would be displayed: -
Gas concentration
(% Volume) Reading shown in
‘VOL’ mode Reading shown
in ‘EXP’ & ‘LEL’ modes
0.5% 0.5% 10
1.25% 1.25% 25
2% 2% 40
2.75% 2.75% 55
Configuration is carried out using the PGD2 Interface Unit in conjunction with a PC running the configuration software available as an
optional accessory.
6.19 Confidence Bleep
The instrument can be configured to operate with or without a “confidence bleep” which is a visual and audible indication to the user
that the instrument is operational. Configuration is carried out using the PGD2 Interface Unit in conjunction with a PC running the
optional configuration software.
Where the “confidence bleep” is selected to be on, the time interval between bleeps is normally set at 10 seconds but can be set to an
alternative interval if required using the configuration software.
The red lens and the green power indicators flash in conjunction with the confidence beep.
6.20 User Identification
Instruments can be given unique user identification codes in addition to the serial number allocated during manufacture. This provides
a means to instantly identify instruments for example by user, site, company, hirer etc.
The user identification is programmed into the instrument using the PGD2 Interface Unit in conjunction with a PC running the optional
configuration software.
The identification can consist of up to 8 alphanumeric or other standard keyboard characters and is shown on the instrument display
preceding the serial number. for example :-
ZEROING SENSORS
PLEASE WAIT
PGD SERIAL No.
A. SMITH 16105