Girevik, Ron,
Please allow me to put on my Critic's hat, one of the most useful functions that I seem to serve here. There is no personal disrespect meant here. These are only my opinions. I see some minor difficulties with each of your wiring schemes.
First, when the Stop pushbutton is pressed, power would be removed from the Reverse function. Even if the drive is stopping, power should be maintained on the Reverse terminal so that the drive does not try to reverse direction while powering to a stop. Many drives would go into fault mode, signaling a Current Overload if the drive tries to reverse while the motor is spinning. However, some drives have built-in protection against a sudden direction reversal.
Second, the PLC Stop function only works when the PLC R1 relay is enabled. It should work at all times. For safety, the PLC should have the ability to stop the drive, even in non-PLC control mode. You cannot predict what students will try. "STOP" should always perform the stop function, no matter when.
Third, both schemes would require PLCHacker to unwire BOTH terminals of the Stop button, moving it to a new location in the circuit. Why complicate the problem (without gaining any benefits)?
Please allow me to put on my Critic's hat, one of the most useful functions that I seem to serve here. There is no personal disrespect meant here. These are only my opinions. I see some minor difficulties with each of your wiring schemes.
First, when the Stop pushbutton is pressed, power would be removed from the Reverse function. Even if the drive is stopping, power should be maintained on the Reverse terminal so that the drive does not try to reverse direction while powering to a stop. Many drives would go into fault mode, signaling a Current Overload if the drive tries to reverse while the motor is spinning. However, some drives have built-in protection against a sudden direction reversal.
Second, the PLC Stop function only works when the PLC R1 relay is enabled. It should work at all times. For safety, the PLC should have the ability to stop the drive, even in non-PLC control mode. You cannot predict what students will try. "STOP" should always perform the stop function, no matter when.
Third, both schemes would require PLCHacker to unwire BOTH terminals of the Stop button, moving it to a new location in the circuit. Why complicate the problem (without gaining any benefits)?
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