KNF N 922 EX Betriebsanleitung Seite 60

Diaphragm Pumps N 922 EX
X Adjusting screw
Translation of Original Operating- and Installation Instructions, english, KNF N 922 EX 08/18
7.1. Information on switching pump on and off
Switching pump on
The pump may not start up against vacuum of 800 mbar abso-
lute or a pressure of 0.5 bar g during switch-on. This also
applies in operation following a brief power failure.
 Make sure that no lower or higher pressures are present in the
lines during switch-on.
Switching pump off
 KNF recommends: When transferring aggressive media, flush
the pump prior to switch-off (see Section 8.2.1) to increase the
service life of the diaphragm.
7.2. Setting the flow (.29-version)
Tools
Quantity Tool/Material
1 Screwdriver blade width 6.5 mm
Tab. 12
 The diaphragm pump is designed so that the flow rate can be
adjusted to suit the analysis system it is supplying. If it is nec-
essary to adjust the flow, proceed as follows (Fig. 9):
To reduce the flow
 Turn the adjusting screw X anti-clockwise.
To increase the flow
 Turn the adjusting screw X clockwise.
When the valve is closed as well as completely opened the
resistance to turning increases noticeably – to avoid damage
do not turn beyond this point.
The corresponding end position is reached.
Fig. 9: Setting the flow (N 922 FT.29E EX)
Operation
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