Preparations Before Startup; Startup; Operating Modes - Grundfos DWK Installation And Operating Instructions Manual

5.4.2 GU01 and GU02
GU01 is a device that monitors the stator temperature
and water penetration into the motor. It receives a
digital signal.
GU02 is a device that monitors the stator and bearing
temperature as well as water penetration into the
motor. It receives an analog signal.
Both monitoring devices must be connected to the
control panel through a relay.
GU01 and GU02 are manufactured for Grundfos. For
further information, contact Grundfos.
LC 231 and LC 241 controllers can handle the same
sensors as GU01 and GU02 but cannot give an
alarm.
For further information, see the data sheets for GU01
and GU02 at www.grundfos.com.
WARNING
Electric shock
Death or serious personal injury
‐
Both monitoring devices must be
connected to the control panel through
a relay.

6. Preparations before startup

Before starting the product:
• Make sure that the product is not connected to the
power supply.
• Make sure that the impeller can rotate freely by
turning it by hand.
Wear protective gloves when touching
the impeller.
• Check the condition of the oil.
• Check the direction of rotation.
• Make sure that the monitoring units, if used, are
operating.
• Check the setting of the level- and float switches
or electrodes.
WARNING
Electric shock
Death or serious personal injury
‐
Before working on the pump, make
sure that the main switch is switched
off and locked in position 0. Make sure
that the power supply cannot be
switched on unintentionally.
Related information
6.3 Checking the direction of rotation
7.2 Oil check and change
16

6.1 Startup

The pump must not run dry.
In case of abnormal noise or vibration,
stop the pump immediately. Do not restart
the pump until the cause of the fault is
identified and eliminated.
If star-delta starting is used, keep the
switching transient time to a minimum to
avoid high transient torques.
DANGER
Rotating elements
Death or serious personal injury
‐
Before manual startup or changeover
to automatic control, make sure that no
persons are working on or near the
pump.
To start the pump, proceed as follows:
1. Switch on the power supply.
2. Open the isolating valves, if fitted.
3. Make sure that the pump is at least 2/3
submerged into the pumped liquid.
4. Tilt the pump by the lifting chain to vent it and
relieve any trapped air.
5. Run the pump briefly and check the liquid level. A
correctly vented pump lowers the liquid level
quickly.
6. Start the pump.
Use hearing protection when working nearby an
installation in operation with a sound pressure level
above 70 dB(A).

6.2 Operating modes

The pumps are designed for intermittent operation
(S3). When DWK.O pumps are completely
submerged in the pumped liquid, they can also
operate continuously (S1). DWK.E and DWK.H
pumps do not have to be fully submerged for S1
operation.
CAUTION
Hot surface
Minor or moderate personal injury
‐
The pump must be at least 2/3rd
submerged into the pumped liquid at
all times.
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