9.5
7.0 -
VFT/MBB FEATURE DESCRIPTION
Utilising the "F" function button enables simple selection of one of the below modes. When the LED is energized and
flashing next to the mode required, the operator must adjust the value "N" using the
is confirmed by pressing the START/STOP button.
MANUAL Mode
Unit runs at flow rate set on "N" - adjustable 10-100%
1XN Mode
Let's see how the pumps works with an example:
- Pump set in water meter 1XN mode
- Set value on "20"
- At the time the water meter gives a pulse to the pump, it starts its 20 dosing injection strokes, if during this phase
further shuts of the contact occur, these are neglected. Ended up the 20 injections, the pump is waiting for further
pulses from the water meter to restart the dosing cycle.
1XN(M) Mode
The pump is operated by an impulse produced by an external device (e.g. pulse emitting water meter) and it supplies
a number of injections equal to the value visualized on the display "N" (set by the operator). The injections are distributed
with a variable frequency that depends by the time passed between a water meter pulse (produced by water meter)
and the other.
Possible impulses (contacts) that may arrive to the pump while is already dosing are saved in the memory of
the microcontroller, these will be delivered after the first batch is dosed.
Let's see how the pump works with an example:
The pump receives the first contact and returns a string "N" injections to the maximum frequency (e.g. 120 imps./min).
To the arrival of the second contact, the pump computes the time "T" spent by the arrival of the first one and it returns
a string of "N" injections not more to the maximum frequency but to that it allows to uniformly distribute them in the
time "T".
In case such time reduces, the pump keeps into consideration the injections "N1" which have not been delivered and
add them to the "N" ones still not delivered. There are no problems if the time occured between the contacts should length.
If instead quick contacts occurs and it goes to condition N1>4 times N, the pump goes in alarm (on the display AL3 is
visualized) but continues working and maintaining all the parameters set before by the operator but not dosing
the strokes related to the last water meter pulses "N".
1:N Mode
The pump supplies an injection of chemical only when it has reached a number of pulses (contacts), equal to the value
visualized on the display (set by the operator)
Let's see how it works with an example:
- Pump set with water meter 1:N
- Set value on "20"
- While the water meter supplies 20 pulses the pump discharge 1 stroke.
PRIMING (100% flow)
is possible in all meter modes by pressing and holding
simultaneously.
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