CENTENT CN0170, Руководство по оборудованию

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CENTENT MOTION CONTROLLER
The step motor drive should run the motor in the direction indicated by the
"CW/CCW" indicator LED. If the direction is the opposite of this, it can be
reversed by switching the step motor's phase leads.
The DIR output can sink 50 milliamps when in the logical '0' state. It is
compatible with TTL and 5 volt CMOS logic. It is also directly compatible
with opto-isolated step motor drive inputs. The DIR output driver is shown
in Figure 5.
ISET: (pin 2)
The ISET output, in conjunction with the IRET (pin 1), is used as an option
to set the step motor current to a lower, stand-by level while the motor is
at rest. This is possible only if the step motor drive has provisions for a
current set input. In many applications the torque required from the motor
is substantially less when the motor is stationary. By reducing the motor
current during idle, a dramatic decrease in motor and drive heating can be
achieved.
The CN0170 waits a programmed period after a motor has stopped to
activate the ISET output. If the motor is commanded to move before this
time delay elapses, the timer is reset and the ISET output does not
activate.
When the ISET output is active, the
"STANDBY PWR" indicator LED lights. The
ISET output and "STANDBY PWR"
indicator turn off 4 milliseconds before
step pulses are sent to the drive. This
delay permits the motor current to rise to
its normal operating level before a move
begins. The ISET output circuit is shown
in Figure 6.
Figure 6, ISET output
5