Delta Tau Geo MACRO, User Manual And Reference Manual

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Geo MACRO Drive User Manual
32 Connections
Connecting Main Feedback Sensors (X1 & X2)
X1 is for motor #1 and X2 for motor #2.
Digital Quadrature Encoders
Quadrature encoders provide two digital signals that are a function of the position of the encoder, each
nominally with 50% duty cycle, and nominally one-quarter cycle apart. This format provides four distinct
states per cycle of the signal, or per line of the encoder. The phase difference of the two signals permits the
decoding electronics to discern the direction of travel, which would not be possible with a single signal.
Typically, these signals are at 5V TTL/CMOS levels, whether single-ended or differential. The input
circuits are powered by the main 5V supply for the controller, but they can accept up to +/-12V between
the signals of each differential pair, and +/-12V between a signal and the GND voltage reference.
Differential encoder signals can enhance noise immunity by providing common-mode noise rejection.
Modern design standards virtually mandate their use for industrial systems, especially in the presence of
PWM power amplifiers, which generate a great deal of electromagnetic interference.
Hardware Setup
The Geo Drive accepts inputs from two digital encoders and
provides encoder position data to the motion processor. X1 is
encoder 1 and X2 is encoder 2. The differential format
provides a means of using twisted pair wiring that allows for
better noise immunity when wired into machinery.
Geo Drives encoder interface circuitry employs differential
line receivers. The wiring diagram on the right shows an
example of how to connect the Geo drive to a quadrature
encoder.
Function Pin #
ChA+ 1
ChA- 14
ChB+ 2
ChB- 15
ChC+ 3
ChC- 16
2
3
4
5
14
15
16
17
1
6
7
18
19
8
9
20
21
10
11
22
23
12
13
24
25
Quadrature
Encoder
CHA+
CHA-
CHB+
CHB-
CHC+
CHC-
5V
GND
GND
Shield
X1/X2