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13. Cascade mode
The VARIOMAT 2 frequency converters are
prearranged for use in pressure boosting sets with
up to 2 pumps in the version with 2 variable speed
pumps.
13.1 Cascade mode installation
Connect the frequency converters on the delivery
pipes of the pumps, the installation must comply
with the provisions under paragraph 6.
13.2 Cascade mode electrical
connection
Connect the supply cables to the motors and to the
power supply following the instruction under
paragraph 7. The power supply must comply the
provisions of the paragraph 4. The connection with
the power supply must be made with the
interpositions of magnetothermal bipolar switches
C class (one for each frequency converter) with
proper size and with a type A differential switch as
indicated on the paragraph 7.1.
N°
E 1
E 2
E 3
E 4
E 5
E 6
E 7
--
H 1
H 2
C 1
Description
Blockage due to overheating.
Blockage due to low supply volta-
ge or high rectified voltage.
Blockage due to overcurrent in the
frequency converter.
Blockage due to direct short circuit
between the phases of output terminals.
Wrong three-phase motor connection.
Pressure transducer fault.
Blockage due to missing supply
phase
The frequency converter do not
switch on.
Blockage due to no water.
System pressure higher than the
pressure generated by the pump.
Suction difficulties.
Cascade mode communication
error.
Causes
The frequency converter automatically rearms itself
when the temperature fall below the safety level.
The frequency converter automatically rearms itself
when the tension come back in the admitted interval.
The system stops and automatically re-starts
after 1 minute for 3 times.
-
Check the connections.
Pressure transducer spoiled.
Check the connection to the supply line and ten-
sion.
Missing tension, broken fuse, see paragraph 13.
Lack of water in the suction tank. System auto-
matically restarts.
Check the compatibility of the system with the
settings. Check the correct priming of the pump.
Check the RS 485 connection or that both pumps
are enabled.
The frequency converters which are not working are
recognizable from the red led "Failure" blinking. The
frequency converters not able to communicate are
recognizable from the red led turned off.
12. Alarms
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