Operation With Frequency Converter - Wilo Rexa PRO Notice De Montage Et De Mise En Service

6.5.5.3 Sealing chamber monitoring (ex-
ternal electrode)
6.5.6 Motor protection adjustment
6.5.6.1 Direct activation
6.5.6.2 Star-delta activation
6.5.6.3 Soft starter
6.5.7 Operation with frequency con-
verter
Installation and operating instructions Wilo-Rexa PRO
Installation and electrical connection
With PTC sensor
Connect the PTC sensor via an evaluation relay. Relay "CM-MSS" is recommended for
this. The threshold has been preset.
PTC sensor wiring diagram
Temperature limiter
10, 11 PTC sensor connection
Temperature controller and limiter
High temperature connection
11
Centre terminal
10
Low temperature connection
12
Triggering status for temperature controller and limiter
Depending on the version of the thermal motor monitoring, the following triggering
status must occur when the threshold value is reached:
▪ Temperature limiter (1 temperature circuit):
The system must be deactivated when the threshold is reached.
▪ Temperature controller and limiter (2 temperature circuits):
When the threshold for the low temperature is reached, the motor can deactivate with
automatic reactivation. When the threshold for the high temperature limit is reached,
the motor must deactivate with manual reactivation.
Note the additional information in the section on potentially explosive areas in the
appendix!
Connect the external electrode via an evaluation relay. Relay "NIV 101/A" is recommen-
ded for this. The threshold is 30 kOhm.
Once the threshold is reached, a warning must be output or the unit must be
switched off.
CAUTION
Connection of the sealing chamber control
If on reaching the threshold, there is only a warning, the pump could be irreparably
damaged by the water ingress. Deactivation of the pump is always recommended!
Motor protection must be set depending on the selected activation type.
At full load, set the motor protection switch to the rated current (see rating plate). At
partial load, it is recommended to set the motor protection switch 5 % above the cur-
rent measured at the duty point.
The motor protection setting depends on the installation:
▪ Motor protection installed in the motor line: Set the motor protection to 0.58 x the
rated current.
▪ Motor protection installed in the mains supply cable: Set the motor protection to the
rated current.
The maximum start-up time in star connection is 3 seconds.
At full load, set the motor protection switch to the rated current (see rating plate). At
partial load, it is recommended to set the motor protection switch 5 % above the cur-
rent measured at the duty point. The following points must also be observed:
▪ Power consumption must always be below the rated current.
▪ Complete starting and stopping within 30 s.
▪ To avoid power dissipation, bypass the electronic starter (soft start) once normal oper-
ation is reached.
Operation on the frequency converter is permitted. Refer to the appendix for the relev-
ant requirements!
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