Grundfos BMS Series - Checking the Power Supply; 7 Commissioning the Product

7. Commissioning the product
These commissioning guidelines concern both fresh-water
installations and systems for desalination.
WARNING
High sound pressure level
Death or serious personal injury
‐ Use hearing protection.
WARNING
Pressurised system
Death or serious personal injury
‐ Be aware of pressurised pipe systems even after
shutdown.
Commissioning of BMSX booster systems must be performed by
Grundfos technicians or by audited partners acting as service
suppliers for Grundfos.
Furthermore, we recommend that the commissioning of BMS hs,
BMS xl and BMS hp systems is performed by Grundfos technicians
or audited partners.
Commissioning includes report and on-site training of the people
who will be responsible for maintaining and monitoring the system.
Related information
5.4 BMSX system
7.1 Checking the power supply
1. Supply voltage
1
2
3
TM001371
Measure the voltage between the phases
with a voltmeter.
Connect the voltmeter to the terminals of
the frequency converter.
When the motor is loaded, the voltage must be within ± 5 % of the rated
voltage. If the voltage varies more than that, the motor may burn.
If the voltage is constantly too high or too low, replace the motor with a motor
that corresponds to the supply voltage.
Large variations in the supply voltage indicate a poor power supply, and you
must stop the pump until the defect has been found.
It may be necessary to reset the frequency converter.
2. Current
consumption
TM001372
Measure the current of each phase while
the pump is operating at a constant outlet
pressure, if possible at the performance
where the motor is most heavily loaded.
For information on the normal operating
current, see the nameplate of the motor.
The difference between the current of the phase with the highest current
consumption and the one with the lowest current consumption must not
exceed 10 % of the lowest current consumption.
If it does, or if the current exceeds the full-load current, check these possible
faults:
• A damaged pump is causing the motor to be overloaded. Pull the pump
out of the sleeve for overhaul.
• The motor windings are short-circuited or partly disjointed. The motor
must be repaired.
• Too high or too low supply voltage.
• Poor connection in conductors. Weak cables. Replace cables if
necessary.
In case a further motor check is required, proceed as follows:
• BMS hs or BMS xl with PM or AC motor: Disconnect the
frequency converter and lock the shaft of the PM motor. Even
unpowered, a motor with permanent magnets will generate
voltage if rotated.
• BMS hp with MG or MGE motor: Follow the instructions in the
installation and operating instructions for the MG or MGE motor.
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English (GB)