Danfoss iSave 50, Operating Manual

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Operating guide | iSave 50 - 70
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180R9357 | AQ265943679828en-00100
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IOM iSave 50 - 70 | 0
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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 (see data sheet)
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 sufficient start torque
Choose a VFD that is designed for sufficient
start torque. See guide line 180R9372
Ramp-up settings in the VFD are not cor-
rect. VFD is tilting
Set ramp-up parameters correct. See guide
line 180R9372
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 opera-
tion
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 performance
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 neces-
sary
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
Pressure on the membranes (5) is too low 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 lowpressure side.
• The water in all connected pipes must be
drained.