Homa CTP 50 M, Оригинальное руководство пользователя

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7.3 Automatic Float Switch Control
The pumps may be supplied with float switch level control-
lers. They start and stop the pump according to the
liquid level in the pit.
The difference in level between start and stop must be ad-
justed by adjusting the free swinging length of the cable
between the float switch and the cable fastening. Long
cable end: Large difference in level. Short cable
end: Small difference in level.
The stop level must be adjusted in such a way, that the
pump stops before the liquid level is lowered below the
top of the pump volute.
The start level must in any case be below the bottom of
the liquid inlet pipe of the pit.
The high alarm level, if a separate float switch for that is
installed, should be adjusted approx. 10 cm above the
start level, in any case it must be below the bottom of the
liquid inlet pipe of the pit, so that the start level must be
adjusted accordingly.
Never place the float switch in the sump without fixing the
float switch cable to a fixed point i the sump, because the
float switch needs a rotation around the fixing point of the
cable to operate without any problems. Non-observance
may cause an overflow because the pump does not start
running or a dry run of the pump in fact that the pump
does not stop, which will destroy the pump.
Information for the operation with explosion classifi-
cation (Ex-class) pumps:
Ex-pumps in A design will be supplied with control box
and floatswitch. Floatswitches do have self protecting cir-
cuit. Manufactured and marked as such. Dry run and sip
operation has to be avoid. Switch-of-level has to be
choosen that the hydraulic is filled or covered always with
the medium.
8. Start-Up
Never let the pump run dry for a long time of period,
as it will destroy the pump (danger of overheating).
Start the pump, when the system has been filled with
liquid and vented. Open the isolating valves. Check the
position of the float switches. If necessary, check the di-
rection of rotation of the pump, as described under 6.5.
Put the switch on the control box to the required mode of
operation.
9. Maintenance and Repair
Before maintenance or repair disconnect the pump
from the power supply to avoid accidental starting of the
pump!
Before carrying out maintenance and service, the
pump must be thoroughly flushed with clean water. Rinse
the pump parts in clean water after dismanteling.
In case of a defect of the pump, a repair shall be car-
ried out only by the manufacturer or through an authorized
workshop. Conversions or alternations of the machine/unit
are permittes only after arrangement with the manufac-
turer. Only HOMA spare parts shall be used.
In accordance with the product liability law we point
out that we shall not be liable for damages caused by our
product due to unauthorized repair by persons other than
the manufacturer or an authorized workshop or due to the
use of spare parts other than original HOMA parts. The
same product liability limitations are valid for accessories.
When unscrewing the inspection screw of the oil
chamber, please note that pressure may have built up in
the chamber. Do not remove the screw until the pressure
has been fully relieved.
Before maintenance or repair make sure that all rotat-
ing parts stand still!
Pumps running under normal operation conditions should
be inspected at least once a year. If the pumped liquid is
very muddy or sandy or if the pump is operating continu-
ously, the pump should be inspected every 1.000 operat-
ing hours.
For long and trouble-free operation of the pump, following
points should be checked regularly:
- Nominal current (A): Check with amp-meter.
- Pump parts: Check for possible wear. Replace defective
parts.
- Ball bearings: Check the shaft for noisy or heavy opera-
tion (turn the shaft by hand). Replace defective ball bear-
ings. A general overhaul of the pump is usally required in
case of defective ball bearings or poor motor function.
This work must be carried out by an authorized service
workshop.
- Cable entry: Make sure that the cable entry is watertight
and that the cables are not bent sharply and/or pinched.
- Oil level and oil condition in oil chamber: The oil be-
comes greyish white like milk if it contains water. This may
be the result of defective shaft seal. The oil should be re-
placed after 3000 operating hour. Oil type: degradable
HOMA-ATOX.
When the pump is new or after replacement of the shaft
seals, check the oil level after one week of operation.
- Mechanical seals: Check the mechanical seals for wear-
out.
Return of pumps
If a pump has been used for a liquid which is injurious
to health or toxic, the pump will be classified as contami-
nated.
If HOMA is requested to service the pump, HOMA must
be contacted with details about the pumped liquid, etc.
before the pump is returned for service. Otherwise HOMA
can refuse to accept the pump for service (see attach-
ment).
Possible costs of returning the pump are paid by the cus-
tomer. However, any application for service (no matter to
whom it may be made) must include details about the
pumped liquid if the pump has been used for liquids which
are injurious to health or toxic.