PEDROLLO E2 TRI - Mode 5 - Pressurising; Water Detection via cosφ (Dry Running) and Pump Management via Pressure Transducer

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| ENGLISH
MODE 5 – PRESSURISING
4-20
mA
4-20
mA
Amperometric
pressure
transducer
4-20 mA
Ratiometric
pressure
transducer
0-10 V
Factory conguration
Parameter
to be congured
Value
P1 3.5 bar
ΔP1 0.5 bar
P2 2.5 bar
ΔP2 0.5 bar
COSFI ON
REC TIME 2 min
MAX REC T 60 min
Pressure transducer
Water detection via cosφ (dry running) and pump management via
pressure transducer
The pressure transducer controls operation of the two pumps, turning them
on or o according to the value measured in the system. The cosφ of the
pumps will also be monitored to generate a dry running alarm when ap-
propriate.
If the pressure drops to P (read)<(P1-ΔP1), either one pump or the other
starts running according to the alternating logic and the control panel then
checks the cosφ.
If the following control logic has been selected:
– DRY LOGIC=COS (default) and
cosφ (read)>cosφ (set min)
or
– DRY LOGIC=CURR and
CURR (read current)>CURR MIN (set min current)
it means that the pump is operating with water in the system, so the control
panel lets it run, otherwise it is stopped due to dry running.
If the pressure drops to P (read)<(P2-ΔP2) again, the other pump starts
running (if there are two) and the control panel then checks the cosφ of the
second pump, using the same logic as for the rst one.
When the pressure rises to P (read)>P2 again, the second pump is switched o, leaving the rst one running (if there are
two). If the pressure rises to P (read)>P1, the pump that was left running is also switched o.
PRESSURE
PUMP 1
P1-∆P1
P2
PUMP 2
P2-∆P2
t (sec)
P (bar)
ON
ON
ON ON
ON ON
OFF
OFFOFF
OFF
P1
PRESSURE
PUMP 1
P1-∆P1
t (sec)
P (bar)
ON ONOFF
P1