Step 5. Make Connections To Encoder; Step 6. Configure Amplifier - Galil Motion Control CDS-3310 User Manual

Step 5. Make Connections to Encoder

Step A. Connect Encoder Wires to 15-pin high density J2 ENCODER
Step B. Verify proper encoder operation.

Step 6. Configure Amplifier

Step A. Set the amplifier Gain
Step B. Set the Error Limit
Step C. Set Torque Limit
CDS-3310
The CDS-3310 accepts single-ended or differential encoder feedback with or without an index
pulse. Match the leads from the encoder you are using to the encoder feedback inputs. The
signal leads are labeled MA+ (channel A), MB+ (channel B), and IDX+ (index). For
differential encoders, the complement signals are labeled MA-, MB-, and IDX-.
NOTE: When using pulse and direction encoders, the pulse signal is connected to channel A
and the direction signal is connected to channel B. The controller must be configured for
pulse and direction with the command CE (see command reference).
Once it is connected, turn the motor shaft and interrogate the position with the instruction
TPA <return>. The controller response will vary as the motor is turned.
At this point, if TPA does not vary with encoder rotation, there are three possibilities:
1. The encoder connections are incorrect - check the wiring as necessary.
2. The encoder has failed - using an oscilloscope, observe the encoder signals. Verify
that both channels A and B have a peak magnitude between 5 and 12 volts. Note
that if only one encoder channel fails, the position reporting varies by one count
only. If the encoder failed, replace the encoder. If you cannot observe the encoder
signals, try a different encoder.
3. There is a hardware failure in the controller - connect the same encoder to a different
controller. If the problem disappears, you probably have a hardware failure. Consult
the factory for help.
Select the amplifier gain that is appropriate for the motor. The amplifier gain command AG
can be set to 0, 1, or 2 corresponding to 0.4, 0.7, and 1.0 A/V.
Usually, there is uncertainty about the correct polarity of the feedback. The wrong polarity
causes the motor to run away from the starting position. Using a terminal program, such as
Galil SmartTerminal, the following parameters can be given to avoid system damage:
ER 2000 <CR> Sets error limit on the A axis to be 2000 encoder counts
OE 1 <CR> Disables A axis amplifier when excess position error exists
If the motor runs away and creates a position error of 2000 counts, the motor amplifier will be
disabled.
Peak and continuous torque limits can be set through TK and TL respectively. The TK and
TL values are entered in volts on an axis by axis basis. The peak limit will set the maximum
voltage that will be output from the controller to the amplifier. The continuous current will
set what the maximum average current is over a short time interval. The following figure
captured with WSDK is indicative of the continuous and peak operation. In this figure, the
continuous limit was configured for 2 volts, and the peak limit was configured for 10 volts.
Chapter 2 Getting Started
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