Auxiliary Pumps During Constant Pressure Control - Pentax IPFC-Serie Betriebsanleitung

8. Auxiliary pumps during constant pressure control

When the water needs vary considerably, it is advisable to share the water request between several pumps ensuring better
efficiency and reliability.
A first method consists of a single pump driven directly by IPFC and another 1 or 2 pumps directly connected to the mains
DOL (Direct On Line); DOL pumps are controlled by IPFC and connected to the mains through 1 or 2 contactors.
In this method, DOL pumps are not started and stopped smoothly with the corresponding increase in energy consumption
and mechanical wear (startup current). Also note that DOL pumps are not protected by IPFC.
A second method of sharing water demand (named COMBO mode) consists of using additional pumps in parallel (up to 8),
with each one driven by a IPFC.
In this method, energy consumption and reliability of the pumping system is maximized: IPFC monitors and protects each
pump. It is possible to assemble a booster system composed of pumps connected in COMBO mode and another 1 or 2 DOL
pumps to cover additional water demand (menaged only by master).
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If pumps cosphi is lower than the dry-running cosphi for at least 2 seconds, IPFC will stop the
pump. IPFC will try to run the pump every 10, 20, 40, 80, 160 minutes and then the pump is
stopped.
ATTENTION: if dry-running protection occurs, IPFC will try to start the pump automatically.
Be sure to cut power supply before attempting maintenance
IPFC will stop the pump if the input motor current is higher than the set motor current for an
extended time. By pressing the START button it is possible to run the pump again.
IPFC will stop the pump if the input voltage is higher than the set voltage for an extended
time. By pressing the START button it is possible to run the pump again. IPFC will stop the
pump if the input voltage is lower than the set voltage for an extended time. By pressing the
START button it is possible to run the pump again.