ABB ACQ810-04, Hardware Manual, Page: 62 / 144

62 Planning the electrical installation
Connecting a motor temperature sensor to the drive I/O
WARNING! IEC 60664 requires double or reinforced insulation between live
parts and the surface of accessible parts of electrical equipment which are either
non-conductive or conductive but not connected to the protective earth.
To fulfil this requirement, the connection of a thermistor (and other similar components) to
the digital inputs of the drive can be implemented in three alternate ways:
1. There is double or reinforced insulation between the thermistor and live parts of the
motor.
2. Circuits connected to all digital and analog inputs of the drive are protected against
contact and insulated with basic insulation (the same voltage level as the drive main
circuit) from other low voltage circuits.
3. An external thermistor relay is used. The insulation of the relay must be rated for the
same voltage level as the main circuit of the drive. For connection, see Firmware
manual .
Example circuit diagram
See page 139 .