Guidelines for planning the electrical installation 67
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, ypu can connect a thermistor (and other similar components) to
the inputs of the drive:
• If there is double or reinforced insulation between the thermistor and live parts of the
motor or
• if 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.
Another way is to use an optional thermistor protection module or an external thermistor
relay. The insulation of the relay must be rated for the same voltage level as the main
circuit of the drive. For connection to the relay, see the firmware manual. For connection to
the thermistor protection module, see its manual.
See also sections
• AI1 and AI2 as Pt100, Pt1000, Ni1000, KTY83 and KTY84 sensor inputs (X1) on page
89
• CMOD-02 multifunction extension module (external 24 V AC/DC and isolated PTC
interface) on page 166
• CPTC-02 ATEX-certified thermistor protection module, (external 24 V AC/DC and
isolated PTC interface) on page 172.
Example circuit diagram
See page 137.