Operating Modes; Start And Stop Levels - Grundfos AP40-70 Montage- Und Betriebsanleitung

CAUTION
Hot surface
Minor or moderate personal injury
‐
Do not touch the surface of the pump
while it is running.

6.1 Operating modes

Never use these pumps for siphoning
operation. The pumps must always be
completely submerged in the pumped
liquid.
The pumps are designed for continuous (S1)
operation. In this operating mode, the pump can
operate continuously without being stopped for
cooling. Being completely submerged, the pump is
sufficiently cooled by the surrounding liquid. During
S1 operation, the maximum number of starts per
hour is 15.
The pumps must be completely
submerged for continuous operation.
P
1
2
S1 operation
Position Description
1 Operation
2 Stop
The minimum liquid level is at the top of the pump
housing.
For AP40 and AP50 pumps,
intermittent (S3) operation between 40°C and 60°C
liquid temperature is permitted up to 30%. S3
operation is a series of 10-minute duty cycles. Each
cycle has a 3-minute period of constant load followed
by a 7-minute period of rest. Thermal equilibrium is
not reached during the cycle.
Minimum liquid level
Position
1
P
1
t
2
S3 operation
Position
1
2
3

6.2 Start and stop levels

Start and stop levels can be adjusted by changing the
free cable length of the float switch.
Long free cable = large difference in level.
Short free cable = small difference in level.
• To prevent air intake and vibrations, install the
stop level switch, so the pump is stopped before
the liquid level reaches the upper edge of the
clamp.
1
Description
Minimum liquid level
3 t
Description
Operation
Stop
Duty cycle
13