Connecting Encoder And Encoder Interface Unit - ABB IRC5 Applications Manual

2.2.1.4. Connecting encoder and encoder interface unit

Overview
If the cable from the robot to the encoder is too long, the inductance in the cable will produce
spike pulses on the encoder signal. This signal will over a period of time damage the opto
couplers in the encoder interface unit.
See Product manual - IRC5 for details on connecting to the encoder interface unit.
Reduce noise
To reduce noise, connect the encoder with a screened cable.
Reduce spike pulses
To reduce spike pulses, install a capacitor between the signal wire and ground for each of the
two phases. The correct capacitance value can be determined by viewing the encoder signal
on an oscilloscope.
The capacitor:
Encoder power supply
The encoder is normally supplied with 24 VDC from the encoder interface unit.
When connecting two encoder interface units to the same encoder, let only one of the encoder
interface units supply power to the encoder. If both encoder interface units supply power, a
diode must be installed on each of the 24 V DC connections to make sure the power supplies
do not interfere with each other.
Connecting encoder and the synchronization switch
The following procedure describes how to install the encoder and the synchronization switch
to the encoder interface unit.
3HAC18154-1 Revision: F
• should be connected on the terminal board where the encoder is connected.
•
values are 100 nF - 1 µF, depending on the length of the cable.
•
One encoder can be connected to several encoder interface units.
•
each controller must have an encoder interface unit if more than one robot is to use the
sensor.
Action
1. Connect the encoder to the encoder interface
unit (DSQC 377) on the controller.
2 Machine Synchronization
2.2.1.4. Connecting encoder and encoder interface unit
Illustration
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