Xylem Aquavar, Instruction Manual

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speed. The ETR function calculates the motor temperature that is based on actual current
and speed. The calculated temperature is visible as a readout parameter in [16-18] Motor
Thermal in the frequency converter.
Motor Thermal Protection can also be achieved using an external thermistor. Set [1-90]
Motor Thermal Protection to data value [2] Thermistor trip or data value [1] Thermistor
warning. Set [1-93] Thermistor Source to the input to which the thermistor is connected.
Refer to the examples below for wiring details.
The thermistor cut-out value is >3kΩ. Integrate a thermistor (PTC sensor) in the motor for
winding protection.
Figure 2: The characteristics of Thermistor resistant
The following examples show various ways to connect the PTC/Thermistor to the drive.
• Using a digital input and the 24 V as a power supply.
– Parameter set-up:
– Set [1-90] Motor Thermal Protection to Thermistor Trip [2]
– Set [1-93] Thermistor Source to Digital Input 19 [4]
3 Product Description
Aquavar ® Intelligent Pump Controller - 150 HP to 600 HP INSTRUCTION MANUAL 13