ABB ACS480 - AI and AO (or AI, DI and +10 V) as PTC Motor Temperature Sensor Interface

AI2
AGND
+24V
DGND
4…20 mA
+
-
P
I
Process actual value measurement or reference, 0(4)…20 mA, R
in
= 137 ohm. If the sensor power
supply comes through its current output circuit, use 4…20 mA signal, not 0…20 mA.
AI2
AGND
Auxiliary voltage output, non-isolated, +24 V DC, max. 250 mA+24V
DGND
AI2
AGND
+24V
DGND
(0)4…20 mA
+
-
OUT
P
I
Process actual value measurement or reference, 0(4)…20 mA, R
in
= 137 ohmAI2
AGND
Auxiliary voltage output, non-isolated, +24 V DC, max. 250 mA+24V
DGND
AI and AO (or AI, DI and +10 V) as PTC motor temperature sensor interface
WARNING!
IEC 60664 and IEC 61800-5-1 require double or reinforced insulation between
live parts and accessible parts when:
• the accessible parts are not conductive, or
• the accessible parts are conductive, but not connected to the protective earth.
Obey this requirement when you plan the connection of the motor temperature
sensor to the drive.
If the motor temperature sensor has a reinforced insulation vs. the motor windings, you can
connect it directly to the drive IO interface. This section shows two connection alternatives
for the direct I/O connection. If the sensor has no reinforced insulation, you must use another
type of connection to fulfill the safety requirements. See Implementing a motor temperature
sensor connection (page 48).
See the firmware manual for information on the related Motor thermal protection function,
and the required parameter settings.
PTC connection 1
1…3 PTC sensors can be connected in series to an analog input and an analog output. The
analog output feeds a constant excitation current of 1.6 mA through the sensor. The sensor
resistance increases as the motor temperature rises, as does the voltage over the sensor.
The temperature measurement function calculates the resistance of the sensor and generates
an indication if overtemperature is detected. Leave the sensor end of the cable shield
unconnected.
Electrical installation – North America 81
11