4.3
Operating modes
Installation and operating instructions Wilo-Rexa PRO
Product description
External monitoring devices
Sealing chamber
Key: - = not available/possible, o = optional, • = as standard
All monitoring devices fitted must be connected at all times!
Monitoring of motor compartment
The motor compartment monitoring protects the motor winding from short-circuits. The
moisture is measured by an electrode.
Monitoring the motor winding
The thermal motor monitor protects the motor winding from overheating. Bimetallic strips
are installed as standard for the temperature measurement. As an option, the temperature
can also be measured with PTC sensors. The design of the thermal motor monitoring de-
pends on the motor:
▪ P 13 motor:
The thermal motor monitoring is designed as a temperature limiter. When the temperature
is reached, deactivation with reactivation lock must take place.
▪ P 17 motor:
The thermal motor monitoring is designed as a temperature controller. This allows the mea-
surement of two temperatures. When the low temperature is reached, an automatic reacti-
vation can be initiated after cooling the motor. When the high temperature is reached, the
unit must deactivate with reactivation lock.
External monitoring of the sealing chamber
The sealing chamber can be equipped with an external pencil electrode. The electrode regis-
ters fluid ingress through the mechanical seal on the fluid side. An alarm or deactivation of
the pump can therefore take place through the pump control.
Operating mode S1: Continuous duty
The pump can operate continuously at the rated load without exceeding the permissible
temperature.
Operating mode S2: Short-time duty
The maximum operating period is specified in minutes, e.g. S2-15. The pause must last until
the machine temperature is no more than 2 K away from the temperature of the coolant.
Operating mode S3: Intermittent periodic duty
This operating mode defines a switching cycle at the ratio of operating time and standstill
time. The given value (e.g. S3 25 %) refers to the operation time. The switching cycle has a
duration of 10 min.
If two values are given (e.g. S3 25 %/120 s), the first value refers to the operation time. The
second value indicates the maximum time of the switching cycle.
Operating mode: Non-immersed operation
The "non-immersed operation" operating mode describes the possibility of the motor
emerging during the drainage pumping sequence. This allows a further lowering of the water
level as far as the upper edge of the hydraulics. Observe the following points during non-
immersed operation:
▪ Operating mode
– P 13 motor:
The motor can be run non-immersed in "non-immersed" operating mode.
– P 17 motor:
In "non-immersed" operating mode, running the motor non-immersed is not permitted!
▪ Max. fluid and ambient temperature: The max. ambient temperature corresponds to the
max. fluid temperature shown on the rating plate.
P 13
P 17
o
o
en-US
13