Grundfos Dosing monitor, Installation And Operating Instructions Manual

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2.1 Definitions
Correct dosing stroke: A pulse from the dosing
monitor corresponds to the internal stroke signal
within acceptable time.
Incorrect dosing stroke: There is no pulse from the
dosing monitor corresponding to the internal stroke
signal within the acceptable time (the pump is not
pumping).
2.2 Logic
If two incorrect dosing strokes are performed, the
pump will continue operating, but it will change over
to alarm mode, like in the case of "low level". The red
indicator light will be on and the alarm output, if any,
will be activated (variant AR).
For each correct stroke the counter is reset and the
alarm output, if any, is deactivated.
2.3 Operation with vent valve
Fig. 2
It is possible to achieve a self-acting solution for liq-
uids which may cause gas accumulation by using an
automatic vent valve together with the dosing moni-
tor and an alarm output (control variant AR). The
alarm output can thus activate the vent valve, which
automatically vents the gas accumulated in the dos-
ing head. When the dosing head has been vented,
the pump will start pumping again, the alarm output
will be deactivated and the vent valve will close.
TM
02
40
99
48
01
N
F
NO C
N
F