Extracting The Smoke Gas - Wohler RP 72 Operating Manual

Taking the sample
6.2 Extracting the
smoke gas
Fig. 4: Extracting the smoke gas
22
Do 10 pump strokes as follows:
Pull out piston (20) slowly (in about 2-3 sec-
•
onds) and hold it in the final position for about
3 seconds, so that a pressure compensation
can be made.
ATTENTION!
Through the filter paper the pressure compensa-
tion can only take place slowly. Therefore it is ab-
solutely necessary to wait 3 seconds before
pressing the piston back.
• Press the piston back.
• Repeat this procedure 10 times.
ATTENTION!
Waiting times, with pulled up piston should strictly
be kept, so that the pump can draw the right
amount of flue gas.
• Take the measuring head with the extraction
probe (1) out of the check opening.
• Remove the clamps (2) from the measuring
head (4).
Remove the filter paper and analyze the soot-
•
spot on the paper as explained in chapter 5.3
.
NOTE!
The excentrical check opening of the measuring
head (1) allows several tests with the same paper
moving the filter paper.