The standard configuration of the AEN signal is TTL active high. In other words,
the AEN signal will be high when the controller expects the amplifier to be enabled.
The polarity and the amplitude can be changed if you are using the ICM-1900
interface board. To change the polarity from active high (5 volts = enable, zero volts
= disable) to active low (zero volts = enable, 5 volts = disable), replace the 7407 IC
with a 7406. Note that many amplifiers designate the enable input as ‘inhibit’.
To change the voltage level of the AEN signal, note the state of the resistor pack on
the ICM-1900. When Pin 1 is on the 5V mark, the output voltage is 0-5V. To
change to 12 volts, pull the resistor pack and rotate it so that Pin 1 is on the 12 volt
side. If you remove the resistor pack, the output signal is an open collector, allowing
the user to connect an external supply with voltages up to 24V. The user should
provide current limiting resistors in this case.
Step C.
Connect the encoders
For stepper motor operation, an encoder is optional.
For servo motor operation, if you have a preferred definition of the forward and
reverse directions, make sure that the encoder wiring is consistent with that
definition.
The DMC-1600 accepts single-ended or differential encoder feedback with or
without an index pulse. If you are not using the AMP-19x0 or the ICM-1900 you
will need to consult the appendix for the encoder pinouts for connection to the
motion controller. The AMP-19x0 and the ICM-1900 can accept encoder feedback
from a 10-pin ribbon cable or individual signal leads. For a 10-pin ribbon cable
encoder, connect the cable to the protected header connector labeled X ENCODER
(repeat for each axis necessary). For individual wires, simply match the leads from
the encoder you are using to the encoder feedback inputs on the interconnect board.
The signal leads are labeled CHA (channel A), CHB (channel B), and INDEX. For
differential encoders, the complement signals are labeled CHA-, CHB-, and INDEX-
.
Note:
When using pulse and direction encoders, the pulse signal is connected to
CHA and the direction signal is connected to CHB. The controller must be
configured for pulse and direction with the command CE. See the command
summary for further information on the command CE.
Step D.
Verify proper encoder operation.
Start with the X encoder first. Once it is connected, turn the motor shaft and
interrogate the position with the instruction TPX <return>. The controller response
will vary as the motor is turned.
At this point, if TPX 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 axis. If the problem disappears, you probably have a hardware failure.
Consult the factory for help.
Step E.
Connect Hall Sensors if available.
14
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Chapter 2 Getting Started
DMC-1600
