ABB ACQ550-U1-011A-6, User Manual

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ACQ550-U1 User’s Manual 135
Parameters
Group 35: MOTOR TEMP MEAS
This group defines the detection and reporting for a particular potential fault – motor
overheating, as detected by a temperature sensor. Typical connections are shown
below.
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, connect a thermistor (and other similar components) to the
drive’s control terminals using any of these alternatives:
• Separate the thermistor from live parts of the motor with double reinforced
insulation.
• Protect all circuits connected to the drive’s digital and analog inputs. Protect
against contact, and insulate from other low voltage circuits with basic insulation
(rated for the same voltage level as the drive’s main circuit).
• Use an external thermistor relay. The relay insulation must be rated for the same
voltage level as the drive’s main circuit.
The figure below shows thermistor relay and PTC sensor connections using a digital
input. At the motor end, the cable shield should be earthed through, eg a 3.3 nF
capacitor. If this is not possible, leave the shield unconnected.
Motor
T
Motor
T
T T
One sensor
Three sensors
AI
1
AGND
AO
1
AGND
AI
1
AGND
AO
1
AGND
3.3 nF
3.3 nF
Motor
T
Motor
T
Thermistor
relay
Control board
DI6
+24 V DC
Control board
DI6
+24 V DC
3.3 nF
Thermistor relay
3501
SENSOR TYPE
= 5 (
THERM
(0)) or 6 (
THERM
(1))
PTC sensor
3501
SENSOR TYPE
= 5 (
THERM
(0))