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Commissioning
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WILO GVA GmbH 2019-02
–
Intermittent operation – has upstream soft starter been installed?
–
Have the min./max. temperatures of the fluid been tested?
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Has the max. immersion depth been tested?
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Has the minimum water immersion of the propeller been defined and is this mon-
itored?
7.6
Switch on and off
The mixer must switch on and off using a separate operating point (on/off switch,
switchgear) set by the customer.
During the start process, the rated current is exceeded for several seconds. Current
consumption continues to be slightly above the rated current until the operating tem-
perature of the motor is reached and the flow in the basin increases. During regular op-
eration, the rated current should no longer be exceeded.
CAUTION! If the mixer does
not start up, switch off immediately. Remove the fault before reactivating!
7.7
During operation
WARNING
Risk of burns from hot surfaces!
Motor housing can become hot during operation. It may cause burns. Allow the mo-
tor to cool down at ambient temperature after switching it off!
CAUTION
Incorrect operation can cause material damage!
The propeller must always be immersed during operation. If the fluid level drops be-
low the required immersion level, switch off the mixer! We therefore recommend in-
stalling a level monitoring device for applications where the fluid level fluctuates
significantly!
NOTICE
Take note of additional literature!
To ensure proper use, additionally read and observe the manufacturer instructions.
During operation, observe the locally applicable regulations on the following topics:
ƒ
Workplace safety
ƒ
Accident prevention
ƒ
Handling electrical machines
Strictly comply with the personnel responsibilities specified by the operator. All person-
nel are responsible for ensuring compliance with responsibilities and regulations!
Check the following points at regular intervals:
ƒ
Operating voltage*
ƒ
Frequency*
ƒ
Current consumption between individual phases*
ƒ
Voltage difference between the individual phases*
ƒ
Max. switching frequency*
ƒ
Minimal immersion in water of the propeller
ƒ
Quiet/low-vibration running
*Tolerance specifications as per manufacturer’s instructions!
Increased current consumption
Depending on the fluid and the flow, the current consumption may vary slightly. If cur-
rent consumption is elevated for a longer period, this indicates a change in conditions
and will lead to increased wear of the mixer. The cause for a change in conditions could
be:
ƒ
Propeller blade setting angle too steep. Check settings and adjust if necessary.
ƒ
A change in the viscosity and density of the fluid.
ƒ
Insufficient mechanical pre-cleaning, e.g. fibrous and abrasive content.
ƒ
Non-homogeneous flow conditions due to fixtures or deflections in the operating
space.
