Homa CHRS.../4 series, Оригинальное руководство пользователя

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In the case that in the explosion-protected submersible
motor pumps electrical monitoring sensors are installed
outside the enclosed chamber, then their control circuits
must be carried out inside the motor by the manufacturer
in the ignition protection type intrinsic safety „i“ according
to EN 60079-11:2007.
A potential equalization is installed in the whole intrinsical-
ly safe circuits. A further grounding of the ex-intrinsically
safe circuits is not permissible. The use of this equipment
may only be carried out in the ex-area of the device group
II category 2 when certified ex-intrinsically safe electrode
relays are used and an intrinsically safe circuit of the igni-
tion protection type EX [ib] with the following values has
been used:
• Ui = 28 V max
• Ii = 300 mA max
• Pi = 1.3 W max
The effective internal inductivity Li and the capacity Ci are
negligibly small. In automatic operation with float swit-
ches, these must be installed according to VDE 0165 as
intrinsically safe circuits in the ignition protection type
intrinsically safe „i“ and connected to an ex-intrinsically
safe transistor relay.From motor sizes AM303 there is
built in as standard and in accordance with previously de-
scribed protective measures, each a conductivity probe
and a magnetic buoyancy floating switch (only for vertical
operation) in the oil bearings. A temperature excess above
130°C (T4) at the seals as well as at the housing surface
is safeguarded according to the measures mentions in
Section 4.3!
Caution! In ex intrinsically safe circuits the instru-
ment lines are marked in blue.
8.5.3. Operating off the grid
It is also absolutely necessary that for operating off the
grid to install with thermally delayed excess power trig-
gers also temperature limiters with the strand designa-
tions T1 and T2 to the controls in accordance with the
connection diagram!
8.5.4. Frequency converter operation
For frequency converter operation it is absolutely neces-
sary to install an arrangement for direct temperature mo-
nitoring. This consists of a PT thermistor built into the coil
according to DIN 44 082 and a function-tested triggering
device according to RL 94/9/EG.
The excess power protection arrangement is to be seen
here as additional monitoring. The power limitation of the
converter is set at the highest to 3 x the motor current.
8.5.5. Potential equalization
It is possible for equalization flows (stray or leakage cur-
rents) to flow intermittently or continuously in electrically
conducting plants or components. For this purpose it is
necessary to install a potential equalization in accordan-
ce with EN 60079-14. On the ex-protected HOMA sub-
mersible motors there are installed an outer connection
of min 4 mm2 to max. 6 mm2 for creating a potential
equalization. Further application information for this is to
be taken from the applicable country explosion protection
ordinances.
Installation information for the mechanical part
Caution! The fluid cover of the pump hydraulic must
be monitored by a leveling control!
8.5.6. Danger due to spark generation
Mechanically generated sparks can ignite flammable ga-
ses and condensates. According to EN 1127-1 Para. 6.4.4,
sparks must also be excluded for category 2 in normal
operation. In normal operation no spark generation is pos-
sible due to fluid covering (medium covering of the pump
hydraulic). The ingress or suction of foreign bodies (sto-
nes, pieces of metal, etc) through the suction nozzles into
the pump hydraulic is not possible in an expected case
of malfunction in which the enclosure fails as the pump
cannot suck up pumping medium nor its containing solids.
In the ventilated shaft, the explosion-protected submer-
sible motor pumps are drained via a drain system with
two guide tubes of galvanized steel, between their guide
claws of grey cast iron that guide it into the automatic cou-
pling arrangement. The guide velocity, with max 0.1 m/s
(10 cm/s) is so low that no sparks can be generated even
in the most disadvantaged conditions. In the first installati-
on, the guide claws of the drain arrangement should be lu-
bricated with ball bearing grease in order to suppress heat
and spark generation in the most disadvantaged case.
8.5.7. Danger due to hot surfaces
Hot surfaces can only occur in the case of an expected
malfunction. Here an operational heating to a maximum of
70% of the temperature classification limit T4 (135°C) can
be expected. However. If, in the case of a malfunction,
the temperature limit is reached, then the temperature
monitoring of the electric motor, which is connected with
the mechanical part (pump) by means of a common shaft
will force the whole unit to be separated from the grid.
Caution! As a preventive measure for the occurrence
of temperatures at the mechanical part of the sub-
mersible motor above the temperature classification
T4, a level safety system with a safety-integrity level
SIL2 is to be installed and checked. (see Chap. 4). The
safety system is to be programmed and switched
such that an operation of the unit is only permitted
with a prescribed medium cover of the pump hydrau-
lic of a minimum of 0.2 m.
8.5.8. Danger due to static charge
Under certain circumstances, electrostatic charge can
release flammable discharges. The HOMA explosion-pro-
tected submersible pumps contain no rechargeable insu-
lated conducting components such as plastics. In addition,
there is an external connection for generating the poten-
tial equalization which must be installed by the user. If
further components or elements installed in the ex-zone,
then the user is required as the most important measure
according to EN1127-1Para 6.4.7, to undertake the linking
and grounding of all conducting parts and substances.