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Examples
Booster unit
Problem: no stop of the HYDROVAR
Parts to check
Solution
•
existing demand
•
non return valve is not closed
•
pre charge pressure in the pressure tank
•
no correct settings of WINDOW and
RAMPHYSTERESIS
•
shut down RAMP too slow
•
suction line too long
•
check pipes and valves
•
change non return valve
•
adjust according the diagram
•
set WINDOW (ca.10%) and
RAMPHYSTERESIS (80-50%)
•
set RAMP 2 to 4...15 sec.
•
the MINIMUM FREQUENCY should be
activated for pressure increase at 0 demand
Control on constant flow
Problem: control fluctuations
Parts to check
Solution
control characteristics are set to low
enlarger WINDOW and RAMPHYSTERESIS to
99% to control with RAMP 3 and 4
Circulating pump
Problem: oscillation of the motor speed
Parts to check
Solution
control settings too fast
•
increase RAMP 3 and 4: 100...200sec
•
WINDOW (ca.20%) and
RAMPHYSTERESIS (ca.99%)
Problem: ACTUAL VALUE can't be hold
Parts to check
Solution
Ramphysteresis too big
RAMPHYSTERESIS: 90-99%
Submersible pumps
Problem: motor cables are too long
Solution: reduce SWITCHING FREQUENCY, BOOST: 10-20%
General
Problem: pressure fluctuations, analogue signal not constant
Solution:
•
check cables and connection of the screen
•
check earth connection of the Transmitter
•
use screened cables