Start Level Set; Thermal Switches - Grundfos SEG AUTOADAPT Montage- Und Betriebsanleitung

9.3 Start level set

The pump start level may be affected by the
barometric pressure. In the case of long intervals
between start and stop, the start level may differ
from the set level. See examples below.
Example 1: Constant barometric pressure
The pump starts when the liquid level in the pit has
reached the set start level. Then the pump will run
until the liquid level reaches the stop level. When it
stops, the pump will calibrate itself in relation to the
actual barometric pressure. See fig. 7.
Barometric pressure
Fig. 7 Example 1: Constant barometric
pressure
Example 2: Rising barometric pressure
If the barometric pressure rises after the pump has
stopped, the pump will register this rise as a rise in
liquid level. The result may be that the pump starts
before the set start level is reached. See fig. 8.
Barometric pressure
Fig. 8 Example 2: Rising barometric pressure
Start level set
Stop level
Start level set
Stop level
Example 3: Falling barometric pressure
If the barometric pressure falls after the pump has
stopped, the pump will register this fall as a fall in
liquid level. The result may be that the pump starts
after the set start level was reached. See fig. 9.
Therefore, the distance between the pump stop level
and the inlet to the pit should be at least 50 cm. See
fig. 6.
Barometric pressure
Fig. 9 Example 3: Falling barometric pressure
Warning
The pump incorporates dry-running
protection based on two dry-running
sensors placed on either side of the
electronic unit. If a dry-running sensor
detects water shortage, the pump stops
immediately and cannot restart until the
sensors are fully submerged again.
The sensors must be cleaned at regular
intervals, depending on the deposits of
sludge on the sensors in the pit.

9.4 Thermal switches

All pumps have two sets of thermal switches in the
stator windings.
When a thermal switch is activated, the
pump stops immediately and will not
restart until the motor windings have
cooled sufficiently.
If the pump does not restart automatically,
Note
the pump must be reset and restarted
manually. See section
pump.
If the pump has to be restarted manually
repeatedly, contact Grundfos or an
authorised service workshop.
Start level set
Stop level
10.4 Resetting the
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