Grundfos DME, Installation And Operating Instructions Manual

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4.8 Operating modes
NOTE: The displayed gal, l and ml values are only
reliable if the pump has been calibrated to the actual
installation, see section
6.
The pump can run in five different operating modes:
•
Manual
• Pulse
• Analog
• Timer (internal batch control)
• Batch (external batch control).
See description in the following sections.
4.9 Manual
The pump is dosing as constantly and evenly as pos-
sible, without any external signals.
Set the quantity to be dosed in gph, l/h or ml/h. The
pump automatically changes over between the mea-
suring units.
* The figures in brackets indicate the maximum ca-
pacity when the anti-cavitation function is acti-
vated.
Fig. 6 Manual mode
4.10 Pulse
The pump is dosing according to an external pulse
signal, i.e. a water meter with pulse output or a con-
troller.
Set the quantity to be dosed per pulse in ml/pulse.
The pump adjusts its capacity according to two
factors:
• Frequency of external pulses.
• The set quantity per pulse.
Setting range:
DME 2:
0.000018 ml/pulse - 5 ml/pulse
DME 8: 0.000069 ml/pulse - 15 ml/pulse
DME 12: 0.000111 ml/pulse - 24 ml/pulse
DME 19: 0.000204 ml/pulse - 37 ml/pulse
DME 48:
0.00530 ml/pulse - 96 ml/pulse
Fig. 7 Pulse mode
If the set quantity per pulse multiplied by the pulse
frequency exceeds the pump capacity, the pump will
run at maximum capacity. Excess pulses will be
ignored and the "actual capacity" display will flash.
4.11 Analog
The pump is dosing according to an external analog
signal. The dosed quantity is proportional to the input
value in mA.
4-20 (default):
4 mA = 0 %.
20 mA = 100 %.
20-4: 4 mA = 100 %.
20 mA = 0 %.
0-20: 0 mA = 0 %.
20 mA = 100 %.
20-0: 0 mA = 100 %.
20 mA = 0 %.
See fig. 8.
The capacity limitation will influence the capacity.
100 % corresponds to the maximum capacity of the
pump or the set maximum capacity, see section
4.15 .
Setting range
U.S. Gallons Metric
DME 2
0.00066 -
0.66 (.47*) gph 2.5 ml/h -
2.5 (1.8*) l/h
DME 8
0.0020 -
1.98 (1.47*) gph 7.5 ml/h -
7.5 (5.6*) l/h
DME 12
0.0032 -
3.17 (2.37*) gph 12 ml/h -
12 (9*) l/h
DME 19
0.0049 -
4.88 (3.83*) gph 18.5 ml/h -
18.5 (14.5*) l/h
DME 48
0.0127 -
12.68 (9.77*) gph 48 ml/h -
48 (37*) l/h
Set value
Set quantity in
ml/pulse
Actual capacity in
gph, ml/h or l/h
Grundfos.bk Page 14 Wednesday, May 21, 2008 11:21 AM