ABB ACH480, Руководство по оборудованию

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PTC connection 2
If no analog output is available for the PTC connection, it is possible to use a voltage
divider connection. 1…3 PTC sensors are connected in series with 10 V reference and
digital and analog inputs. The voltage over the digital input internal resistance varies
depending on the PTC resistance. The temperature measurement function reads the
digital input voltage through the analog input and calculates the PTC resistance.
T
T T
DIn
AIn
+10 V
1
2
3
DGND
DCOM
1…3 PTC sensors 1
Digital input and analog input. Set the analog input type to V (volt) in parameter group
12 Standard AI . Define the temperature sensor type, signal source, etc. with parameters
35.11…35.24 . For the sensor type, select: PTC AI/DI Voltage Divider tree . Make sure that
the digital input is not configured to any other use by parameters.
2
10 V reference voltage 3
AI1 and AI2 as Pt100, Pt1000, Ni1000, KTY83 and KTY84 sensor inputs
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 the 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 56) .
You can connect temperature measurement sensors (one, two or three Pt100 sensors;
one, two or three Pt1000 sensors; or one Ni1000, KTY83 or KTY84) between an analog
input and output as shown below. Leave the sensor end of the cable shield unconnected.
104 Electrical installation – North America