64 Guidelines for planning the electrical installationConnecting a motor temperature sensor to the drive I/OWARNING! IEC 60664 requires double or reinforced insulation between live partsand 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, you can connect a thermistor (and other similar components) tothe inputs of the drive:• if there is double or reinforced insulation between the thermistor and live parts of themotor or• if circuits connected to all digital and analog inputs of the drive are protected againstcontact and insulated with basic insulation (the same voltage level as the drive maincircuit) from other low voltage circuits.Another way is to use an optional thermistor protection module or an external thermistorrelay. The insulation of the relay must be rated for the same voltage level as the maincircuit of the drive. For connection to the relay, see the firmware manual. For connection tothe thermistor protection module, see its manual.See sections• AI1 and AI2 as Pt100, Pt1000, Ni1000, KTY83 and KTY84 sensor inputs (ANALOGIN/OUT) on page 86• CMOD-02 multifunction extension module (external 24 V AC/DC and isolated PTCinterface) on page 162• CPTC-02 ATEX-certified thermistor protection module, (external 24 V AC/DC andisolated PTC interface) on page 168.