Startup; General Startup Procedure; Operating Modes - Grundfos SL1 Installation And Operating Instructions Manual

7. Startup

DANGER
Electric shock
Death or serious personal injury
‐
Before starting work on the pump,
make sure that the fuses are removed
or the main switch is switched off.
Make sure that the power supply
cannot be switched on unintentionally.
Make sure that all protective
equipment is connected correctly. The
pump must not run dry.
DANGER
Crushing hazard
Death or serious personal injury
‐
Do not open the clamp during
operation.

7.1 General startup procedure

This procedure applies to new installations as well as
after-service inspections if the startup takes
place after the pump was placed in the tank.
Check that there is positive inlet pressure
before starting up the pump.
1. Remove the fuses and check that the impeller can
rotate freely. Turn the impeller by hand.
2. Check the condition of the oil in the oil chamber.
3. Check that the system, bolts, gaskets, pipes, and
valves are in correct condition.
4. Mount the pump in the system.
5. Switch on the power supply.
6. Check whether the monitoring units, if used, are
operating appropriately.
7. For pumps with a WIO sensor, switch on the IO
113 and check that there are no alarms or
warnings.
8. Check the setting of air bells, float switches, or
electrodes.
9. Check the direction of rotation.
10. Open the isolating valves, if fitted.
11. Check that the liquid level is above the motor for
S1 operation and above the cable entry for S3
operation. Do not start the pump if the minimum
level is not reached.
12. Start the pump and let it run briefly. Check if the
liquid level is falling.
13. Check if the outlet pressure and input current are
normal. If not, air may be trapped inside the
pump.
To remove trapped air from the pump
housing, tilt the pump by the lifting
chain during operation.
In case of abnormal noise or
vibrations, stop the pump immediately.
Do not restart the pump until the cause
of the fault is identified and eliminated.
After one week of operation or after shaft seal
replacement, check the oil condition in the chamber.
For pumps without sensors, take an oil sample.
Every time the pump is removed from the tank, go
through the above procedure before restart.
Related information
6.7 IO 113
7.3 Direction of rotation
8. Servicing the product
8.2 Dismantling the pump
8.2.1 Oil change
8.4 Oil quantities

7.2 Operating modes

The pumps are designed for intermittent operation
(S3). When completely submerged, the pumps can
also operate continuously (S1).
S3, intermittent operation:
S3 operation is a series of 10-minute duty cycles
(TC). Each cycle has a 4-minute period of constant
load followed by a 6-minute period of rest. Thermal
equilibrium is not reached during the cycle.
In this operating mode, the pump is partly submerged
in the pumped liquid. The minimum liquid level is at
the top of the cable entry.
P
O
A
S
C
S3, intermittent operation
B
t
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