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Unread 29-10-2012, 13:27
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Re: Limit switches on a lift -- best practice

To answer the original question, Joe has it right. Limit switches should be handled at the level of motor control, not at the level of command input.

Quote:
Originally Posted by dyanoshak View Post
This is exactly how the limit switches are handled in Jaguar's firmware...
I'd say rather that this is effectively how the firmware responds to the limit switches. The word "exactly" implies that the schematic shown represents the circuitry in the Jaguar, and that's definitely not the case. The motor drive current doesn't go anywhere near the limit switch connectors. They're just digital I/O connected to the Jaguar's microprocessor.

Effectively, though, the Jaguar does the same thing that the schematic is intended to portray. Activating the forward limit prevents the speed controller from commanding the motor to go forward while still letting it go in reverse, and vice versa.

Last edited by Alan Anderson : 29-10-2012 at 13:30.