Startup; Operating Modes - Grundfos DPK Series Installation And Operating Instructions Manual

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.
Pump operating levels, analog level transmitter and high-level float switch or digital float switches
Pos. Description
S1
S1 operation
S3 S3 operation
FS High-level float switch
LT Level transmitter
SR Start
S Stop
S1
S3
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 completely submerged, the pumps can
also operate continuously (S1).
CAUTION
Hot surface
Minor or moderate personal injury
‐
The pump must be at least 2/3
submerged into the pumped liquid at
all times.
FS
SR
S1
S
S3
LT
S3, intermittent operation
S3 operation is a series of 10-minute duty cycles
(TC): the pump must run for maximum 4 minutes and
stop for minimum 6 minutes. Thermal equilibrium is
not reached during the cycle. In this operating mode,
the pump is partly submerged in the surrounding
liquid. The pump must be at least 2/3
into the pumped liquid.
rd
rd
rd
submerged
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