Operation guide | iSave 40
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180R9239 | AQ299555093252en-001601 | iSave 40 | 09.2022
9. Trouble-shooting
9.1 Safety regulations
The operator ensures that all inspection
and installation work is performed by
authorised, qualified specialist personnel
who are thoroughly familiar with the
manual.
The numbers in () correspond to the preferred system design and P&ID.
Problem
Possible cause
Action
VFD cannot start the iSave at initial
start-up.
VFD is not designed for constant torque.
Choose a VFD that is designed for constant
torque.
VFD cannot deliver 140% start torque.
Choose a VFD that is designed for mini-
mum 140% start torque.
Ramp-up settings in the VFD are not
correct. VFD is tilting.
Set ramp-up parameters correct.
Valve (9) is closed.
Open valve (9).
Pressure in the HP line (5) is too high.
Start the iSave only when the pressure in
the HP line is low.
Torque on iSave is too high during
operation.
Pressure difference from HP-out (5) to
HP-in (10) is too high.
Clean or change membranes.
Debris in the booster pump or iSave.
Clean the system.
Wear in the booster pump or iSave.
Repair or change the parts.
Design of the basic plant does not fit the
performance of the iSave.
Change design to fit the iSave perfor-
mance.
Permeate production is too low (17).
Valves (6), (7), (8) or (16) are leaking.
Repair or change valve(s).
Internal leakage in iSave.
Repair iSave.
HP pump flow (2) is too small.
Correct speed on the HP pump.
Check the HP pump and repair if necessary.
Pressure on the membranes (5) is too high. Fouling on the membranes.
Clean the membranes.
Mixing in the iSave is too high.
Check flow on LP-in (12) and adjust flow.
Flow out of the iSave is too low and causes
a recovery rate that is too high.
Check speed on iSave and change if
necessary.
Booster pump in the iSave is worn out.
Perform service on the VP.
Pressure on the membranes (5) is too low.
Valves (6), (7), (8) or (16) are leaking.
Repair or change valve (s).
Internal leakage in iSave.
Repair iSave.
HP pump flow (2) is too small.
Incorrect speed on the HP pump.
Check the HP pump and repair, if necessary.
Before intervening in the iSave/system;
• The power must be shut off and the
starting device be locked.
• The pressure in the high-pressure lines
must be drained to low-pressure side.
• The water in all connected pipes must
be drained.