Opacity Measuring Chamber 4000 AVL 4000
7-4 Service Manual
7.3 Assembling and Disassembling the Opacity
Measuring Chamber
The measuring chamber consists of 2 symmetrical shell halves which are screwed
together with M4 hexagon socket screws.
• Undo the six screws on each side to open the instrument. Separate the two shell
halves by inserting a screwdriver into the gap between them at the top or bottom (e.g.
at the handle) and prising them apart.
• Then lift the top shell half (as shown in Fig. 7-4) off the bottom one.
All integrated assemblies (Fig. 7-5), except the changeover valve unit, are simply
inserted into this shell half and can therefore easily be removed. Only the changeover
valve unit is fixed to the shell by a self-tapping screw. See next section for details of
the assemblies.
Fig. 7-4
Fig. 7-5
Control cable
connection
Shell hal
Fan
Changeover valve
Receiver
Transmitter Measuring chamber