Delta Tau PMAC Pack, Справочник по аппаратуре

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PMAC-Pack
24 Getting Started
Note:
If PMAC is setup for Sign and Magnitude commands for Stepper motors, the
AENA line functions as the direction line. See the PMAC User's Manual and V-F
Converter manuals for further information on Stepper Motor interfacing.
Amplifier Fault Signal (FAULT/)
This input can take a signal from the amplifier so PMAC knows when the amplifier is having problems,
and can shut down action. The polarity is programmable with I-variable Ix25 (I125 for motor #1) and the
return signal is analog ground (AGND). FAULT/ is pin 2. With the default setup, this signal must actively
be pulled low for a fault condition. In this setup , if nothing is wired into this input, PMAC will consider
the motor not to be in a fault condition.
Flag Connection
PMAC has two inputs for each motor intended for the hardware overtravel limit switches. These lines
must actively be held low (to draw current through the LED in the optoisolator) in order for the motor to
be able to move. This requires the use of normally closed (or normally conducting, if solid state) limit
switches. These inputs are direction sensitive; they only stop movement in one direction.
Note:
PMAC-Pack's limits should be conventionally wired. The POSLIM input should
be connected to the positive end of travel, and the NEGLIM input to the negative
end of travel.
Limit Signals (NEGLIM And POSLIM)
PMAC-Pack has two inputs for each motor intended for the hardware overtravel limit switches. These
lines must actively be held low (to draw current through the optoisolator) in order for the motor to be able
to move. This requires the use of normally closed (or normally conducting, if solid state) limit switches.
These inputs are direction sensitive; they only stop movement in one direction.
The PMAC-Packs optically isolated limits may be wired as either sinking or sourcing. Figure 2-4
illustrates connection of a limit input in a Sinking configuration. When the limit switch is normally
closed, current is pulled through the opto-isolator in the PMAC-PACK to ground. Figure 2-5 illustrates
the connection of a limit input in Sourcing configuration. When the limit switch is normally closed,
current flows through the switch and into the PMAC-Pack’s optoisolator to the Flag Return which is tied
to common. The limit inputs are capable of operation at 12 to 24 DC voltage levels. If you desire to
maintain full isoV should be a separate voltage source. It is possible to operate using the +12V
available on pin 2 of each “Flags” connector as the voltage source. However, it should be noted that this
defeats the isolation circuitry causing the limit circuitry to be referenced to PMAC’s analog ground
(AGND) which is typically shared by the amplifier.
Note:
If the direction input of the encoder is ever changed, the wiring of the limit
switches must be changed as well. It is important to check and re-check the
direction sense of your limit inputs.