Maxima MPG Cod. EM00136006
rev. 1.1
28
−
Selecting the Lower Limit (see Fig. 28)
Once this mode and the lower limit (L) have been selected, when the Prog key is pressed the lower limit is stored
in memory and the letter
H
is displayed, followed by the lower limit (expressed in
mA
) for the current signal
(default 4.0) at which the pump runs at the maximum frequency set. This limit can be changed in 0,1 mA steps by
pushing the
▲
and
▼
keys.
WARNING:
Before selecting the
L
and
H
limits check the actual current levels exiting the generator
used, as in this operating mode the pump only doses between the limits set in order to avoid
unwanted doses should the current generator be damaged or an unconnected input current be
received.
WARNING:
The minimum difference between the
L
and
H
limits is
1 mA
, with
L>H
.
If the pump receives a current that is lower than the
H
value it will not dose. However, the flow rate
displayed will begins to flash indicating the the incoming current is below the lower limit.
If the pump receives a current that is higher than the
L
value it will not dose. However, the flow rate
displayed will begins to flash indicating that the incoming current exceeds the upper limit.
WARNING:
The pump may stop automatically due to a pump cut-out signal emitted by the level
sensor (
Level
icon and
Alarm
LED lit), see par. 3.1.4 “Checking the level of the liquid to be dosed”.
−
Flow Control Function (see Fig. 28)
This can be enabled by pushing the
▲
or
▼
keys, and stored in the memory by pushing the
Prog
key.
Displaying and Operation
On exiting programming the flow rate for the input current signal will be displayed. This can be viewed in
percentage (
P
) or frequency (
F
) mode, which can be selected by holding the
Mode
key down.
The
20..0/4
icon stays on. When displayed as a percentage the
%
icon is also lit. The
STOP
icon must be off
while the pump is running.
The maximum dosage frequency can be changed by pushing the
Mode
key and
▲
or
▼
keys together.
EXAMPLE: Model MPG912 with limits set at L = 14.3 and H = 5.5.
If the pump runs at 100% (maximum frequency) the pump will stop when the input signal is at 14,3 mA or above
and it will work at maximum frequency (240 strokes/min) for signals at 5,5 mA.
If the percentage is set at 80% the pump will stop when the input signal is at 14,3 mA or above and it will work at
the working frequency of 192 strokes/min (0,8 x 240) for signals at 5,5 mA.
Currents of less than 5.5 mA will cause the pump to stop. This fault is indicated by the display flashing.
