4.
Back off all adjusting nuts another half-turn (anti-clockwise).
5.
Place the lower nuts on the studs.
6.
Tighten the lower nuts evenly all around.
The clearance between the impeller and the lower diffuser shall be as little as possible.
Check that the impeller can easily be rotated by hand.
In order for the pump to perform at maximum capacity, the impeller must be adjusted regularly.
Troubleshooting
A universal instrument (VOM), a test lamp (continuity tester) and a wiring diagram are required in order to carry
out troubleshooting on the electrical equipment.
Troubleshooting shall be done with the power supply disconnected and locked off, except for those checks which
cannot be performed without voltage.
Always make sure that there is no one near the pump when the power supply is turned on.
Use the following checklist as an aid to troubleshooting. It is assumed that the pump and installation have formerly
functioned satisfactorily. Electrical work shall be performed by an authorized electrician. Follow local safety
regulations and observe recommended safety precautions.
1. Pump fails to start
Is an alarm signal indicated
Yes
Check the cause:
on the control panel?
- If the stator temperature is high, check that
the cooling system is working and that the
No
Impeller rotates easily.
- If there is a fault in the thermal protectors,
contact a service shop.
Check that the overload protection is reset.
Can the pump be started
Yes
a) Fault in the level equipment (start sensors).
manually?
Clean or replace.
b) Fault in control equipment.
No
Check:
- the control current.
- that all connections are intact.
- relay and contractor coils.
- that the control switch “Man/Auto” makes
contact in both positions.
Is the installation
No
Check:
receiving voltage?
- that the main power switch is on.
- that there is voltage in each phase of the
Yes
supply line.
- that all the fuses have continuity and are tight.
supply line.
- that the overload protection is reset.
- that there is no break in the motor cable.
Is the start capacitor
Yes
Replace.
defective?
(only for 1-phase motor)
