7
6.3 Junction
The junction between the lead cable and the drop cable should be done in order to assure a good electrical continuity (also of the ground wi-
re) as well as a perfect waterproof. Tesla provides, as accessory, a kit of junction which gives the guarantee, if well executed, of a perfect
continuity and waterproof.
Caution: we suggest the installation of the following further protections on the box:
- lightning protection or overvoltage protective device to protect the motor from voltage surges wich may be caused by for instance lightning
or electromagnetic interference.
- anti-dry running protection: this could be executed with opportune level sensors or by other power factor measure devices.
To this porpose Tesla provides a control box equipped with capacitorand protections above mentioned.
GUARDIAN M E: for MICRA 50 M - 75 M and 100 M
GUARDIAN 1 E: for MICRA 50 M, 75 T and 100 T
Naturally, as the capacitor value changes with the different rated powers of the single phase pumps, please specify it at the moment of the
purchase order and please check its value before the installation.
We suggest to firscome a differential relay together with a general magnetotermic switch, for the short circuit protection, to every control box.
7.0 INSTALLATION
The max. diameter of the pump/motor is 72mm.
• Check that the internal diameter of the well is so large to contain a submersible pump of this size. Check also the well with an inside calliper to
ensure unobstructed passage.
•
Caution
: in case of open-well it would be necessary anyway to guarantee (by opportune cooling slive) that the water velocity over the motor
is at least of 0,3 m/s.
• When plastic pipe is being used, the pump should be secured by an unloaded straining wire (in stainless steel it is preferably).
•
Caution
: the pump should absolutely not be dropped anchoring it from the electric cable. Use some bands to anchore the cable along the di-
scharge pipe, due to the weight of the water and to the termal expansion, could cause tears to the electric cable.
• Install every 20 m. on the discharge pipe a non return valve.
•
Installation depht
: the dynamic water level in the well should be guaranteed the pump aspiration covering. In particular it would be neces-
sary to make sure that the minimum dynamic water level of the well is at least 1m over the junction strainer of it. Avoid that the motor will or
could be covered with sand. At least 1.5 m lenght should be guaranteed from the motor to the bottom of the well.
• Slacken the straining wire so that it becomes unloaded and lock it to the borehole seal by means of wire locks.
8.0 STARTING AND RUNNING
• After the installation of the pump, before starting it, make an isolation measure with the help of a megahometer. The isolation resistance for
a motor/pump with the cable (in the well) should be higher than 10 Mohm; for a used but in good condition motor it should be higher than 5
Mohm. Indication lower than 0,5 Mohm indicate some anomaly at the cable or motor isolation.
• Start the pump with the discharged valve closed off to approx. 1/3. If there are impurities in the water, the valve should be opened gradual-
ly as the water becomes clearer. The pump should not be stopped until the water is completely clean, as otherwise the pump parts and the non-
return valve may choke up. Caution: this is a very delicate operation which could compromise the life of the pump. Never stop the pump until
the out coming of completely clean water.
• Check the correct direction of rotation in the three phase pump. This will what will give the higher delivery at the same conditions.
The direction of rotation can be changed (only in the three phase) inverting 2 of the 3 alimentation wires.
• Check that the dynamic water level of the well, at the maximum delivery required, ramains always 1 m over the aspiration strainer.
• To ensure the correct cooling of the motor, it is necessary to avoid the running of the pump in the conditions of max. pressure (completely clo-
sed head) for a period longer than 3 minutes.
Caution.
The liquid can be polluted from loss of mechanical seal lubricating liquid.
If the power supply cable is damaged, must be changed by the manufacturer or by any service.
Summary of Contents for MICRA 50 M
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