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Maintenance and repair
72
WILO SE 2021-10
9.5.3
Visual inspection of the connec-
tion cable
Check connection cable for:
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Bubbles
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Cracks
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Scratches
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Abrasion
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Pinch points
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Changes caused by chemical corrosion
If the connection cable is damaged:
ƒ
Decommission the mixer immediately!
ƒ
Have the connection cable replaced by the customer service!
CAUTION! Material damage! Damaged connection cables cause water to enter the
motor. Water in the motor leads to total damage of the mixer.
9.5.4
Visual inspection of cable brack-
ets and cable tensioning
Check cable brackets and anchoring for material fatigue and shrinkage.
ƒ
Replace worn or defective components immediately.
9.5.5
Visual inspection of the mixer
Check the housing and propeller for damage and wear. If there are defects, observe the
following:
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Repair damaged coating. Order repair kits from the customer service.
ƒ
If components have worn, contact customer service!
9.5.6
Function test of the monitoring
device
The mixer must be cooled down to ambient temperature to test resistances!
9.5.6.1
Test the resistor of the temper-
ature sensor
‡
Ohmmeter available.
1. Measure the resistance.
⇒ Measured value
Bimetallic strip
: 0 ohms (passage).
⇒ Measured value
3x PTC sensor
: between 60 and 300 ohm.
⇒ Measured value
4x PTC sensor
: between 80 and 400 ohm.
▶ Resistance checked. If the measured value deviates from the specification, consult
the customer service.
9.5.6.2
Testing the resistor of the ex-
ternal electrode for sealing cham-
ber control
‡
Ohmmeter available.
1. Measure the resistance.
⇒ Measured values “infinite (∞)”: Monitoring device OK.
⇒ Measured value ≤ 30 kOhm: Water in oil. Change oil.
▶ Resistance checked. If the measured value still deviates after the oil change, con-
sult customer service.
9.5.7
Visual inspection of accessories
Accessories must be checked for:
ƒ
Correct fixation
ƒ
Smooth function
ƒ
Signs of wear, e.g. cracks caused by frequencies
Any defects detected must be repaired immediately or the accessories must be re-
placed.
