Setting Up The Cue Frequency Converter In An Spe System - Grundfos SP Series Installation And Operating Instructions Manual

6.6.4 Connection in the case of unidentified cable
marking/connection
If it is unknown where the individual conductors are to be
connected to the mains in order to ensure the correct direction of
rotation, proceed as follows:
Motors wound for direct-on-line starting
Connect the pump to the mains as is expected to be right.
Then check the direction of rotation as described in section
6.6 Connection of three-phase
Motors wound for star-delta starting
Determine the windings of the motor by means of an ohmmeter
and name the conductor sets for the individual windings
accordingly: U1-U2, V1-V2, W1-W2. See fig. 18.
Fig. 18 Unidentified cable marking/connection - motors wound
for star-delta starting
If star-delta starting is required, connect the conductors as shown
in fig. 15.
If direct-on-line starting is required, connect the conductors as
shown in fig. 16.
Then check the direction of rotation as described in section
6.6 Connection of three-phase
6.6.5 Checking the direction of rotation
The pump must not be started until the suction
interconnector has been completely submerged in
the liquid.
When the pump has been connected to the power supply, check
the direction of rotation:
1. Start the pump and measure quantity of water and head.
2. Stop the pump and interchange two phases.
3. Start the pump and measure quantity of water and head.
4. Stop the pump.
5. Compare the two results. The connection giving the larger
quantity of water and the higher head is the correct one.
6.6.6 Soft starter
Grundfos only recommends the use of soft starters which control
the voltage on all three phases and which are provided with a
bypass switch.
Ramp times: Maximum 3 seconds.
For further details, contact your soft starter supplier or Grundfos.
6.6.7 Frequency converter operation
Three-phase MS motors can be connected to a frequency
converter.
During frequency converter operation, it is not
advisable to run the motor at a frequency higher than
the rated frequency (50 or 60 Hz). In connection with
pump operation, it is important never to reduce the
frequency (and consequently the speed) to such a
level that the necessary flow of cooling liquid past the
motor is no longer ensured.
To
enable the monitoring of the motor temperature, Grundfos recommend that Pt100 or Pt1000 sensor is installed.
12
motors.
motors.
If an MS motor with temperature transmitter is
connected to a frequency converter, a fuse
incorporated in the transmitter will melt and the
transmitter will be inactive. The transmitter cannot be
reactivated. This means that the motor will operate
like a motor without a temperature transmitter.
To avoid damage to the pump part, make sure that the motor
stops when the pump flow falls below 0.1 x rated flow.
Voltage peaks for Grundfos submersible motors should be limited
in accordance with the table below.
Motor type
MS402
MS4000
MS6000 and MS6000P
MMS6
MMS8000
MMS10000
MMS12000
For asynchronous motors:
Permissible frequency ranges:
• 30-50 Hz
• 30-60 Hz.
Ramp times: Maximum 3 seconds from standstill to minimum
frequency and vice versa
For synchronous motors MS6000P:
Permissible frequency ranges:
• 55-100 Hz
• 55-120 Hz.
Ramp times: Maximum 3 seconds from standstill to minimum
frequency and vice versa
Depending on the type, the frequency converter may cause
increased acoustic noise from the motor. Furthermore, it may
expose the motor to detrimental voltage peaks. This can be
abated by installing an LC filter or even better a sinus filter
between the frequency converter and the motor.
For further details, contact your frequency converter supplier or
Grundfos.
7. Setting up the CUE frequency converter in an
SPE system
The SPE system consists of the following:
• SPE pump set
• sine-wave filter
• CUE frequency converter.
The CUE has a start up guide. Follow the instructions on the
display.
For further information regarding safety and advanced settings
see the CUE Installation and operating instruction.
Installation and operating instructions
http://net.grundfos.com/qr/i/98870684
Max. U peak
Max. dU/dt
voltage
650 V
2000 V/μs
phase-phase
850 V
2000 V/μs
phase-phase
850 V
2000 V/μs
phase-phase
850 V
500 V/μs
phase-ground
850 V
500 V/μs
phase-ground
850 V
500 V/μs
phase-ground
850 V
500 V/μs
phase-ground