Homa TP 50, Оригинальное руководство пользователя

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ENGLISH | 35
3.3.5. Pump housing
The pump housing, depending on the model, is supplied
with different connections. This means that the machine
can be connected with the respective pipe system. The
pump housing is also available rubber-coated inside. Some
pump housings are supplied with a cleaning hole lid to
eliminate blockages.
The pump can equipped with a stationary wear ring which
can be found in the intake port. This wear ring determines
the gap between the impeller and the intake port. If this
gap is too big, the performance of the pump decreases
and it can lead to blockages. Therefore, it is possible to
replace the wear ring.
3.3.6. Impeller
The impeller is fastened directly to the motor shaft and
driven by it. The impeller is also available in different ma-
terials (GG, GGG, VA, BZ) or coated with ceramic liquid.
A range of different impeller designs are available:
•
M
: Enclosed single channel impeller, for liquids con-
taining impurities and sludge with solid particles or
long fibres of up to 5%
• K : Enclosed multi channel impeller, for liquids con-
taining impurities and sludge with solid particles of
up to 3%
•
V
: Vortex impeller, for liquids containing a high level
of impurities or fibrous matter and containing gas of
up to 7%
Direction of Rotation Check
All pumps have the correct direction of rotation when con-
necting to a dextrorotatory field (U, V, W -> L1, L2, L3).
HOMA switching devices check the mains for a dextroro-
tatory field. If there is no dextrorotatory field, the red LED
lights up. Two phases are to be swapped at the input of
the switching device. For smaller pumps, the check can
be done by monitoring the starting jolt.
Do do this, put the pump carefully on the floor on its edge
and switch on briefly. Seen from above, the pump slightly
jolts in the correct anticlockwise direction.
The pump has the correct direction of rotation if the pump
moves anticlockwise, as the motor starts in the clockwise
direction when seen from above.
ST
AR
T
REACTION
ROTOR
REACTION
ATTENTION
The direction of rotation
is correct if the
impeller/propeller rotates
in a clockwise manner
when viewing down from
top of the placed unit
ATTENTION
The start reaction is
anti clockwise
Beware of rotating impeller! The rotating impeller can
crush and sever limbs. Never reach into the pump unit or
the moving parts during operation. Switch off the machine
and let the moving parts come to a rest before mainte-
nance or repair work!
It is also possible to check the direction of rotation with
a “Motor and Phase Rotation Indicator”. This measuring
device is held on the outside of the motor housing when
the pump is switched on and indicates the direction of
rotation with an LED.
Seal monitoring for pumps with oil chamber:
Version without cooling jacket or “U” version with cooling
jacket and open cooling circuit:
If the shaft seal on the medium side leaks, water enters
the oil chamber and changes the resistance of the oil. The
conductivity of the oil added is monitored via 2 sensors.
The sensors should be connected via 2 wires (designated
S1 and S2) from the pump connecting cable in the con-
trol system to an evaluation unit with electrically isolat-
ed probe circuit. With the version for use in areas with a
potentially explosive atmosphere, select an electrode re-
lay with intrinsically safe circuit. The response sensitivity
should be adjustable from 0-100 kΩ; standard setting 50
kΩ. Appropriate relays can be purchased from HOMA.
Motor cooling
Motors for submerged operation are cooled by the sur-
rounding liquid.
3.3.4. Sealing
The sealing between pump and motor is carried out by
two separate mechanical shaft seals (silicon-carbide) in
tandem-arrangement. It is made of bearing cover and
pressure cover. It is filled with medical white oil. Separate
large oil chamber, lubricating and cooling the mechanical
seals, forming an extra safety and inspection element.
Control are given by the inspection screw of the bearing
housing, and an optional electronic monitoring.