Delta Tau Geo MACRO, User Manual And Reference Manual

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Geo MACRO Drive User Manual
34 Connections
Sinusoidal Encoders
The Geo Drive with the Interpolator option accepts inputs from two sinusoidal or quasi-sinusoidal
encoders and provides encoder position data to the motion processor. This interpolator creates 4,096
steps per sine-wave cycle. User needs to order the option.
Be sure to use shielded, twisted pair cabling for sinusoidal encoder wiring. Double insulated is the best.
The sinusoidal signals are very small and must be kept as noise free as possible. Avoid cable routing near
noisy motor or driver wiring. Refer to the appendix for tips on encoder wiring.
It is possible to reduce noise in the encoder lines of a motor-based system by the use of inductors that are
placed between the motor and the amplifier. Improper grounding techniques may also contribute to noisy
encoder signals.
Note:
Voltage mode encoders are becoming the more popular choice for machine designs
due to their lower impedance outputs. Lower impedance outputs represent better
noise immunity, and therefore more reliable encoder interfaces.
The Geo Drive uses 1 Vp-p voltage mode encoders only.
Hardware Setup
The differential format provides a means of using
twisted pair wiring that allows for better noise
immunity when wired into machinery.
Sinusoidal encoders operate on the concept that
there are two analog signal outputs 90 degrees out
of phase.
Geo Drives can be used only with the voltage
mode encoder type, and the lines have to be
differential. The wiring diagram to the right
shows an example of how to connect the Geo drive
to a sinusoidal encoder.
Function Pin#
Sin+ 1
Sin- 14
Cos+ 2
Cos- 15
Index+ 3
Index- 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
X1/X2
Sin+
Cos-
Sin-
Cos+
+5V
GND
Shield
In_Therm_Mot
1Vpp A
index
Up Power
0V Supply
Index-
Index+
1Vpp B
Sinusoidal
Encoder