ABB ACS850-04 series, Руководство по оборудованию

Страница: 68 / 164

Planning the electrical installation
68
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 the
firmware manual.
Example circuit diagram
See page 154 .
24 V DC
230 V AC
230 V AC
1
2
3
4
1) Relay outputs; 2) Varistor; 3) RC filter; 4) Diode