KSB Amacan P 500-270 Installation & Operating Manual page 39

Fig. 26: Float switch
5 Installation at Site
CAUTION
Temperature monitoring devices not properly connected
Winding damage!
▷ Never use the Pt100 resistance thermometers as the only means of monitoring
the motor temperature.
5.4.1.4.2 Leakage inside the motor
DANGER
Incorrect monitoring of leakage electrode
Explosion hazard!
Danger of death from electric shock!
▷ Voltages must be < 30 V AC and tripping currents < 0.5 mA.
PE
K 1
9
Wiring of the electrode relay
An electrode fitted inside the motor monitors the winding space (B2) for leakage.
The electrode is intended for connection to an electrode relay (core marking 9).
Tripping of the electrode relay must result in the pump set cutting out.
The electrode relay (K1) must trip the motor at a tripping resistance between 3 and
60 kΩ.
5.4.1.4.3 Mechanical seal leakage
The chamber for mechanical seal leakage is equipped with a float switch (core
identification 3 and 4). The contact (maximum 250 V~/2 A) opens when leakage is
detected in the leakage chamber. Opening of the contact shall trigger an alarm
signal.
5.4.1.4.4 Bearing temperature
The bearings of the pump set are equipped with bearing temperature sensors. The
two sensors are Pt100 resistance thermometers (core identification 15 and 16). They
have to be connected to a temperature control device with a Pt100 input and 2
separate outputs for two different switching points (sensor circuit maximum
6 V/2 mA).
Set the following limits:
▪ Alert at 110 °C
▪ Cut-out of the pump set at 130 °C
Amacan P
9
Position of the electrode
B2
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