Adixen ASM GRAPH D+ - Needle Replacement

G 400
Long distance sniffer probe user manual
GB 01962 -
Edition
03 -
June
08
Filter exchange
(continued)
When you change the filter, we recommend cleaning the needle and
the nipple
(sniffer probe with rigid nipple only):
 Take out the needle with needlenose pliers.
Clean delicately the needle with alcohol and a lint-free cloth.
Clean the rigid nipple with alcohol and compressed dry air .
 Put back the needle.
 Put back the filter with its screw: torque < 1 N.m.
Needle replacement
With this kind of sniffer probe, it is normally not necessary to change
the needle.
For every needle replacement in a sniffer probe, put a new needle
with the
same diameter as the old needle.
3 methods can be used for the new needle adjustment :
1
flowmeter use
2
standard sniffer probe use
3
old needle use
Recommended methods
1
Flowmeter use in order to
measure the flow in the sniffer
probe
2
Standard sniffer probe use as
reference
Assembly to do:
Helium leak
detector
P < 10 mbar
or
Flowmeter
0/100 sccm
Pump
Sniffer probe
connected to
the assembly
This method requires keeping a new
sniffer probe as a standard probe.
Do an auto-calibration in sniffing
mode with the standard sniffer
probe.
Do a
measure of the He in the air
with the standard sniffer probe.
Cut the new needle to 85 mm/3.35 inch. Prepare it (see below “ 3 Use
of
the old needle as a reference“, picture 3 ) and put it correctly in the
nozzle
(see “Needle exchange” §).
5 /8