ECOPROBE 5 - rs dynamics

Response of ECOPROBE 5 PID
unit, in the STANDARD mode, to an
increasing concentration of
contaminant.
The most common type of
ECOPROBE 5 PID unit in the
STANDARD mode’s response to an
increase in the concentration of a
contaminant.
ppm
5000
4000
3000
2000
1000
Fig. 21 - Position of the highest contaminant concentration.
67
PID response - STANDARD mode
0
1 3 5 7 9 11 13 15 17 19 21 23 25
distance m
The graph in Fig. 22 shows a typical example, where the highest contamination is represented by small
“breakdown” values. The measured values along the survey line, increase from the edges to the centre of
the plume. When the concentration is higher than the photo-ionization breakdown limit, the photo-ionisation
process collapses and values of several hundreds ppm are indicated erroneously by the instrument.
ppm
PID response - STANDARD mode
distance [m]
Fig. 22 - Position of the highest contaminant
concentration.
In case of the HI SENS mode (Fig. 23), the measured limit is 100 ppm. Higher values of concentration are
almost always indicated by the message “over” displayed on the screen and the value of 100 ppm is linked
with the measured station. The graph in Fig. 23 shows the position of the highest contamination on a line
using the HI SENS mode.
Response of the PID unit in the
HISENS mode to an increase in the
concentration of a contaminant.
PID ANALYZER
ppm
150
100
50
0
PID response - HISENS mode
1 3 5 7 9 11 13 15 17 19 21 23 25
distance m
Fig. 23 – Position of the highest contaminant
concentration.