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Verfügbare Sprachen
Verfügbare Sprachen
Explosion proof models with motors up to 15 kW have a
set of temperature sensors built-in, with a higher switch-
off temperature, connected to the motor cable, the wire
ends marked T1 and T2. They must be connected to a
special relay in the starter box in order to provide manual
pump re-start.
All explosion proof models have both sets of sensors built-
in, as described above, with wire ends marked T1, T2,
T3. They have to be connected accordingly as described
above. The temperature sensor set must be connected to
the switchgear unit so that it switches off if it overheats.
Switch-off temperature of the sensors:
Stator winding Nor-
Motor
mal
T1+T3 Regulator
AM122...C-2/4pol
140°C
AM136...D-2/4/6pol
140°C
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.
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
For large pumps, the direction of rotation can also be de-
tected by looking through the pressure joint into the pump
chamber. Here you will see the impeller and by briefly
switching on, check the direction of rotation by the coast-
ing of the impeller.
Beware of rotating impeller!
The moving 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 maintenance or
repair work!
Additional the direction of rotation can control by a "motor
& phase rotation indicator" , which must put on the motor
housing of the operating pump.
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
32 | ENGLISH
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.
Seal monitoring in the cable junction chamber:
The cable junction chamber is monitored for moisture
penetration via 2 sensors. The sensors should be connect-
ed via 2 wires (designated S3 and S4) from the pump con-
Stator
winding
necting cable in the control system to an evaluation unit
Ex
with electrically isolated probe circuit. With the version for
T1+T2 Limiter
use in areas with a potentially explosive atmosphere, se-
140°C
lect an electrode relay with intrinsically safe circuit. Appro-
140°C
priate 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, lubri-
cating and cooling the mechanical seals, forming an extra
safety and inspection element.
3.3.5. Pump housing
The pump housing, depending on the model, is supplied
ATTENTION
with different connections. This means that the machine
The start reaction is
can be connected with the respective pipe system. The
anti clockwise
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 sta-
tionary 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. It is partly available in different material grades
(GG, GGG, VA, BZ) and can also be coated with ceramic
liquid.
The impellers have different designs depending on the
pump type:
M:
K:
V:
Enclosed single channel impeller, for liquids containing
impurities and sludge with solid particles or long fibres of up
of up to 5%
Enclosed multi channel impeller, for liquids containing
impurities and sludge with solid particles of up to 3%
Vortex impeller, for liquids containing a high level of impurities
or fibrous matter and containing gas of up tp 7%
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