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Supplement for ex-protected model types
2017/04
010-989
The submersible motor series AM....../..EX are cooled by the pumping medium and are suitable for S1 continuous
operation with fully flooded motor. In order to prevent the surface temperature rising to above the temperature
class specified on the nameplate, the motor section must be flooded at all times. In narrow pump chambers, the
level may be reduced by suction to 0.2 m above the pump section for a max. 10min running time.
There is a min. 4mm² connection installed on the submersible motor pumps for potential equalisation in
accordance with EN 60079-14. The cable is connected to this using a cable lug and the screw locking device at
the connection in a non-self-releasing manner.
All existing thermal, level and detector sensors must always be connected in accordance with the instructions
given in this manual and the enclosed circuit diagram.
Special conditions for safe use
A device for direct temperature monitoring must always be used for inverter operation. This comprises PTC
thermistors in accordance with DIN 44 082 built into the winding with switching temperature in compliance with
Table 1 and a function-tested triggering unit in accordance with directive 2014/34/EU. The switching circuit must
be designed in such a way that the submersible motor is switched off when the limit temperature is reached and
can only be switched back on again manually. When the air gaps of the explosion-proof enclosed chamber are
checked, the manufacturer of the submersible motor must be contacted for the gap dimensions. The air gaps of
the tested submersible motor are smaller than those prescribed by the standard.
The fastening screws of the motor are equipped with special screws made of stainless steel class A2-70.
General instructions for the installation and commissioning of explosion-protected submersible motors
Caution!
Before any activities are started at the installation location of the operating equipment, the operating company
must provide information about the status of explosion hazard. The hazard potential can be assessed on the
basis of an official zone classification or an existing explosion protection document. If necessary, the explosion
protection type of the operating equipment must be compared with the given requirements. In closed rooms or
chambers, sufficient ventilation must be ensured before work is started primarily in order to prevent the existence
of potentially explosive gases.
KESSEL explosion-protected operating equipment may only be used in areas (potentially explosive atmospheres)
for which gases and vapours according to explosion group A and B are applicable in compliance with the
equipment’s certified device group II and category 2G as well as the maximum surface temperature of 135°C for
temperature class T4 (for frequency converter operation 200°C for temperature class T3), in compliance with IEC
60079-0.
Caution!
Installation instructions for the electrical section
In addition to these operating instructions, the special instructions in the annex of the enclosed EC type approval
certificate must always be heeded as listed here again:
10.4.1 Electrical connection
Connection of the supply cable within potentially explosive areas may only be carried out using a suitable ex-
protected terminal box which has been tested and certified.