7.1 Priming and bleeding (with an alpha or Beta pump)
WARNING!
Danger from hazardous substances!
Possible consequence: Fatal or very serious inju‐
ries.
Measure: The bleed valve must be equipped with a
transparent PVC hose (6 x 4 mm). The PVC hose
must be connected to the respective chemical
storage tank so that the leaking chemicals can flow
back into the chemical storage tank during the
bleeding process.
DF2a and DF4a pumps
Priming and bleeding is not required with the self-
priming DF2a and DF4a pumps.
1.
Slightly open the bleed valve of the alpha or Beta metering
pump
2.
Stroke length for the Beta pump
If possible, always operate the Beta pump
with 100% stroke length. Only reduce the
stroke length to values between 100% ...
30% if overdosing frequently occurs (over‐
shooting the measured values).
Note the stroke length of the metering pump and set it to a
stroke length of 100% (only with the Beta pump)
3.
Start the controller using the
[START/STOP] key.
4.
Allow the metering pump to run until the feed chemical leaks
from the bleed valve.
5.
Close the metering pump bleed valve.
6.
If required, re-adjust the stroke length of the Beta pump to
the original value.
Re-start the control process: change to the contin‐
uous display using the Change key and start the
controller using the START/STOP key
7.2 Adjust the flow sensor switching point
Sample water may escape.
1.
Adjust the flow to 50 l/h using the ball valve
2.
Hold the flow sensor in place and loosen the mounting clip a
little
Prime the feed chemical as follows
(for alpha and Beta pumps)
The flow sensor should switch when
the flow falls (flow sensor is con‐
nected as an NC).
Start Up
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