Connection To The Power Supply And Determination Of The Sense Of Rotation; Installation Of Float Switches; Maintenance; Checking And Changing The Oil In The Mechanical Seal Chamber - Zenit DRO Serie Manuel D'utilisation Et D'entretien

4.3 CONNECTION TO THE POWER SUPPLY AND DETERMINATION OF THE SENSE OF ROTATION

All operations connecting the motor pump to the electricity supply must be performed by specialised staff in full compliance
with current regulations.
WARNING: in the electrical connection phase connect the yellow-green earth cable first, then the other connections, as
indicated in chapter 8 "ELECTRICAL CONNECTIONS".
Check that the voltage and the frequency of the power supply are the same as those indicated on the motor pump data plate
and that the power absorbed by the motor pump is less than the maximum current available.
Before installation check that the power line is earthed and complies with current regulations and that the motor pump
cables are undamaged.
To protect the motor pump motor use an overload cutout suited to the electrical characteristics shown on the data plate.
A diagram illustrating the correct supply of the motor pump is supplied in chapter 8 "ELECTRICAL CONNECTIONS".
Before making the definitive connections of three phase motors the sense of rotation of the motor pump must be determined.
To determine the sense of rotation proceed as follows:
- apply the provisions of paragraphs 1.2 and 1.3;
- lay the motor pump on one side in a horizontal position and leave unrestrained;
- connect the yellow-green earth lead and then the live leads temporarily to the solenoid switch;
- make certain there are no persons or objects within one metre of the motor pump;
- press the run button for a very brief period.
- look through the inlet hole and check that the rotor rotates anticlockwise.
If the direction of rotation is not correct, invert any two phase connections at the solenoid switch and try again.
Once the rotation is correct, MARK the connection sequence of the leads.
DEACTIVATE the temporary power connection and install the motor pump in its permanent position.

4.4 INSTALLATION OF FLOAT SWITCHES

If the motor pump is fitted with a float it operates completely automatically. Check that there are no objects which could
impede its movement. It is very important to fix float switches so that the cables cannot interfere with one another, neither
become twisted nor catch on projections inside the well. Float switches should be installed in such a way that the minimum
level is NEVER lower than the top cover of the motor pump. Float switches are best secured to a rigid bracket mounted inside
the well. Once the installation of the motor pumps, control panel and float switches is completed, carry out a final inspection
to check functional efficiency. Check with an ammeter that the motor pump current is within the limits indicated on the data
plate; also that the float switches cut in at the required level.

5. MAINTENANCE

Before inspection and maintenance operations carefully read and apply the safety procedures indicated in
paragraphs 1.2 and 1.3
To ensure regular and long-lasting operation of the motor pump the user must perform regular inspections, periodic
maintenance and replacement of used parts. Monthly inspections are recommended, or every 500-600 working hours.
- check that the supply voltage corresponds to the values indicated on the data plate;
- check that noise and vibrations are at their original levels;
- for three phase motors, use amperimetric pincers to check the absorbances on the three phases are balanced and do not
exceed the values shown on the rating plate.
An exploded view of the motor pump is shown in fig. 2 - 2/a on page 84 - 86.

5.1 CHECKING AND CHANGING THE OIL IN THE MECHANICAL SEAL CHAMBER

Before inspection and maintenance operations carefully read and apply the safety procedures indicated in
paragraphs 1.2 and 1.3
The oil should be changed every 5000-7000 working hours, or at least once a year.
Proceed as follows:
Position the motor pump horizontally.
- Unscrew the plug and drain off the oil into a suitable container, or use an oil aspiration device.
- If the oil is clean, then the mechanical seal is still in good condition and the chamber can be refilled with fresh oil.
- If a very small quantity of water is detected at the bottom of the mechanical seal chamber, this will be due to condensation
and is normal, not a sign of any fault with the mechanical seal.
- If a substantial quantity of water has entered the oil chamber and contaminated the oil, this indicates that the mechanical
seal needs inspecting, and perhaps replacing
- Fill the chamber completely with biodegradable oil, CASTROL HYDROIL P46 or similar, and once full remove 20-25 cc to
ensure a sufficient air cushion in the chamber;
- When finished tighten the plug and re-install the motor pump.
If none of the above is available, exceptionally, common vaseline oil can be used. For maintenance, contact our nearest
service centre.
Any repairs to the motor pump must be carried out by the manufacturer or by specialist personnel. If this is not respected, the
guarantee will be invalidated and the machine may become unsafe.
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