Overload Protection System - Kessel Aqualift F Anleitung Für Einbau, Bedienung Und Wartung

Cable identification
The individual cables of the main pumps cables are marked.
In the case that the cable is shortened, the marking should
be left or the cable should be re-marked in the case that the
original marked portion of the cable is cut off. The electrical
system must meet IEC 364 requirements.
In an explosion risk area, all electrical cable connections
to the power supply cable must be carried out to meet
all explosion proof requirements.
5.5.1 Pumpstation Monitoring Systems
Temperature monitoring
Function description of the thermal monitoring
The pump windings are monitored by twin independent ther-
for Ex protected pumps
mal monitors. The first monitoring system (Bimetal tempera-
ture monitor – cables 20 and 21) will shut down the pump
when a certain temperature has been reached. This monitor
will also restart the pump after the pump has cooled.
In the case that the first monitoring system malfunctions, a
second monitoring system (Bimetal temperature alarm – ca-
bles 21 and 22) will shut down the pump before it exceeds
the maximum allowable explosion proof rated temperature.
The pumps will not restart after they cool down if the second
monitor shuts down the system. In this case the pumpstati-
on must be inspected.
The explosion proof protection for the pumpstation only fun-
ctions when the integrated temperature monitor and tempe-
rature alarm are properly connected to the control unit – as
described later in the manual.
Max operating voltage of the switch is 250 V, max switching
current is 2 Amp cos phi = 1
Cable identification 20, 21 and 22.
5. Electrical connections
5.5.2 Securing of electrical connection cables
The pump power cables must be taught and firmly connec-
ted in the chamber to prevent these cables from being
sucked into the pumps.

5.5.3 Overload Protection System

The motor(s) are protected from overloading by a thermal de-
layed overload protection according to VDE 0660. This is set
to the motor´s current – this is displayed on the control unit´s
shield.
5.5.4 Float Switches
The automatic operation of the pumps is controlled by the in-
cluded float switches. The lowest pump off level is set to a
level above the minimal level – see Section 4.4.
5.5.5 Pump Rotation Check
Never place hands or any objects near the impel-
ler of the pump
The control unit includes a pump rotation monitor. In the
case that the phases are improperly connected, an alarm will
sound. Properly connecting power cables as described in
Section 5.5 will guarantee proper pump rotation.
5.5.6 Potential equalling connection
EN 60 204 regulations regulate potential equalling. Pumps
with an explosion proof rating are equipped with an internal
threaded connection for a M8x20 bolt.
Special requirement for chemically corrosive fluids:
(EX) If the pump unit is used in chemically corrosive fluids
and is the subject to explosion protection requirements, the
terminal provided on the outside of the pump unit must not
be used.
Instead, the PE conductor shall be connected to a flange of
the discharge pipe which is not in contact with the fluid
handled. Make sure that electrical contact is established
between the newly created potential equalization connec-
tion and the pump.
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