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

10.3 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 will start when the liquid level in the tank
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. 6.
Barometric pressure
Fig. 6 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. 7.
Barometric pressure
Fig. 7 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. 8.
Therefore, the distance between the pump stop level
and the inlet to the tank should be at least 50 cm.
See fig. 5.
Barometric pressure
Fig. 8 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 will
stop 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 tank.

10.4 Thermal switches

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