MID-7604/7602 Power Drive User Guide
20
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Limit Switch Terminal Blocks
For end-of-travel limit, home, inhibit input, and inhibit output connections,
MID-7604/7602 axes have a separate, 6-position removable screw terminal
connector block. Figure 10 shows the limit switch terminal block pin
assignments.
Figure 10.
Limit Switch Terminal Block Pin Assignment
(Passive Limit Switch Connection Example)
The inhibit output signal is asserted low from the MID-7604/7602 when an
axis is inhibited. This signal can be useful for actuating mechanical brakes
or for monitoring an axis status. An axis is inhibited if the host bus interlock
circuitry is activated, if the ENABLE switch on the front panel is in the
inhibit position, if the motion controller’s inhibit signal is low, or if the
per-axis inhibit input is actively driven.
The MID-7604/7602 stepper drive remains in a reset state for 500 ms after
the inhibit is deasserted. Therefore, you can lose steps if you attempt to
issue a start motion command within 500 ms from the deassertion of the
stepper drive inhibit. A Kill command asserts the inhibit signal from the
controller and a Halt command deasserts the inhibit signal from the
controller. The yellow LEDs (middle row) and red LEDs (top row) on the
front panel illuminate if an axis is currently inhibited (killed state).
Note
In older versions of the MID-7604/7602, the red status LEDs do not illuminate when
the yellow status LEDs illuminate. This behavior only occurs in newer versions of the
MID-7604/7602.
Execute a halt stop to de-assert the inhibit signal from the controller, after
which you must wait at least 500 ms before executing a start.
Breakpoint and Trigger Terminal Blocks
Both the breakpoint and trigger connectors use a 6-pin removable terminal
block.
The trigger terminal block provides access to the trigger input lines,
shutdown input line, and digital ground. The breakpoint terminal block
1
6
2
3
4
5
Forward Limit
Home Input
Inhibit Input
Digital Ground
Reverse Limit
Inhibit Output
