Sulzer J 205, Руководство по ремонту

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2.3 Insulation test
Disconnect all stator leads from the contactor/terminal
block. Check that the contact points are not burned.
Measure insulation resistance between the different
phase windings, between windings and earth and be-
tween windings and thermal contacts circuit.
The insulation resistance should be measured with
500V megohmeter (megger) and the reading should be
at least 1 MΩ. (Figure 5) If the insulation resistance is
lower, the stator unit should be dried in an oven. If the
stator insulation reading after drying is still low, the sta-
tor unit should be replaced.
The insulation between the separate turns in the wind-
ing should also be checked. This can be done by
measuring the resistance of the phase windings, which
should give the same reading for all three windings for
3-phase motors. For resistance values and wiring dia-
grams check section 10.
Note!
DO NOT MEGGER 1000V PUMPS WITH GROUND
CHECK DIODE (GC) CONNECTED.
2.4 Thermal contacts
The circuit with the three built-in thermal contacts
should by checked for continuity, using an ohmmeter or
buzzer. (Figure 6)
If the circuit is open the defective contact should be
identified by checking each individual thermal contact.
The faulty thermal contact can be bypassed in accord-
ance with the wiring diagram.
Figure 5: Megging of windings
Megohmeter
Contactor
Thermal contacts
Figure 6: Testing of the thermal contacts
Thermal contacts Thermal contacts
Thermal contacts Thermal contacts
Tester
Tester
Tester
Tester