14.
RECOMMENDATIONS FOR CORRECT INSTALLATION
The power supply cables must never ever be twisted, pulled or sharply bent (the minimum curving radius must be 5 times greater than the cable diameter).
The free ends of the cables must be carefully protected against possible infiltrations of water or moisture. During installation, it is particularly necessary
to
Ensure that the free ends of the cables are never able to come into contact with water.
aTTENTION Particular attention must also be paid to the condition of the cable. Even tiny roughened parts can cause liquid to penetrate into the motor
compartment!Before starting the unit in installations liable to freeze, always check that the motor is free to turn and that the pumped liquid
is free to flow.It is essential to comply with the electrical powering and hydraulic characteristics of the electric pump, otherwise its working
life and reliability could be jeopardized.
If the cable (L37 l L38 - L39) is replaced, the screws (L85) that fasten the cable gland (L28 - L29) must be tightened with an 8 Nm torque
value. The cable seal (L50 - L51) is compressed to the correct degree by means of a torque wrench and by modifying the number of
washers (L63 - L64) in the cable gland housing if necessary (number of washers 1). Consult the sections and nomenclature chapter for the
L... references.
Recommendations when building the system
All the safety precautions established by the current laws in force must be complied with when building the accumulation chamber. In particular:
- if the pumped liquid contains, or could give rise to explosive gaseous mixtures, always check that the accumulation tank is well ventilated and that
it does not allow gas to stagnate. The electric pump and relative accessories must be of suitable construction and fit for environments with potentially
explosive atmospheres.
- The electrical equipment installed outside the trap must be protected against inclement weather conditions and possible gas infiltrations from the
trap itself.
- The size of the accumulation chamber must be such as to balance three requirements:
a) the working volume must be such as to limit the number of starts/hour (see utilization features);
b) the time the pump remains at a standstill must be such as to prevent the formation of hard sediments;
c) the minimum immersion depth must allow the motor to be completely submersed (or the pump casing if the cooling jacket is installed; please always
check NPSH). The maximum immersion depth must not exceed 20 m.
- The automatic pump coupling base must be firmly fixed to the bottom of the tank.
- The electric pump intake must always be in the lowest part of the accumulation chamber.
- The fluid reaching the accumulation chamber must not create turbulence as could allow the pump to suck air.
- To prevent obstructions and clogging, it is advisable to check that the speed of the fluid through the delivery pipe is always more than 0.8 ÷ 1 m/s.
When the fluid contains sand, a speed of at least 1.6 m/s is required through horizontal pipes and 2.5 m/s in vertical pipes. To reduce load losses and
wear, it is advisable to never exceed 4 m/s.
- The vertical discharge pipe sections must be reduced to the minimum and the horizontal sections must slightly slope downwards in the direction of flow.
- Cast iron valves are normally used for general requirements with sewage.From a constructional aspect, it is preferable to install a clapet check valve
and flat sluice valves.
- Install a check valve when the delivery pipeline is long.
- When installed on the discharge pipe, the check valve must be mounted possibly in horizontal sections and in an easily accessible position.
15. chaRacTERISTIcS OF ThE FORcEd MOTOR cOOLING SYSTEM
(Electric pump with cooling jacket)
aTTENTION
Standard electric pumps are supplied without cooling jackets. In this case, the only permissible type of installation is with the pump submersed and
with the fluid level at the top of the motor casing.
To lower the minimum level of the fluid in a submersed installation or if the electric pump is to be used in a dry chamber, it must be equipped with a
cooling jacket. In this case, cooling may be achieved in two different ways:
1 - The liquid conveyed by the electric pump is used as cooling fluid. This is what happens when the electric pump is supplied complete with
cooling jacket. Fluid circulation is obtained by the particular hydraulic shape of the shield at the rear of the impeller hub. It is particularly suitable when
the fluids contain a low amount of organic, abrasive or scaling matter.
2 - Cooling is obtained by allowing clean external liquid to circulate. To achieve this configuration, first use a N° 32 wrench to unscrew the two
3/4" Gas plugs (Pos. L75) at the side of the electric pump on the oil reservoir. Insert the two countersunk hex plugs (Pos. L76) supplied with the electric
pump, fully tightening them into the holes. Now connect the hole with the "I" indication to the cooling water inlet tube and the hole with the "O" indication
to the drain pipe. The water used for cooling must be clean with a max. inlet temperature of 40°C, a flow rate of not less than 0.2 l/s and a maximum
inlet pressure of 4 bar. It is advisable to use hose pipes for the terminal section of the cooling water connection.
caprari S.p.a.
K.M150N.. / K.M100N.. / K.W100N.. / K.d200N.. / K.M200P.. / K.d250P..
GB
25