In the known forums I have not found answers for my questions based on my following project:
I want to install for my electronic enclosure....
1. an external reset button
2. an external pause button
3. an external emergency stop button
I have found wiring diagrams for the gshield but not for TinyG.
My configuration: Shapeoko 2 - Tinyg - quiet spindle - 24 an 48 V power supply units (2).
Which pins are to be used with Tinyg v8 for this. Are there experiences with the wiring.
I have found here in the forum some very complex informations to install a reset button. Is it a problem to simply interrupt the main power for the two power suplies (TinyG a. Spindle) with the emergency stop button?
I can't answer most of your questions, but I did get confirmation today that the two pin header next to the reset button is for an external reset button.
1. Jim covered reset.
2. Pause is a command, I don't believe there is a hardware button. What do you use to send GCode? Try Chilipeppr, it supports a Pause function from the computer. Pause is a non-trivial operation, as you want to stop Gcode operation, but keep buffers and calculations intact.
3. Emergency stop == open the 24V tinyG supply circuit.
Quiet Spindle
Did you buy a PWM controller for your spindle? If so, which one?
So what is your plan - ON/Off or PWM/variable speed?
Hi,
using the limit switch input for emergency stop is not really a good idea, because these inputs rely on the software. If the software goes haywire, the emergency stop would be useless.
Personally, I would love to see the emergency handling that I know from bigger controls used for multi-kW motors on autocranes or industrial robots: When an emergency situation occurs (emergency switch, access door opened, limit switch etc), the software gets a signal to shut down all movement as soon as possible in a controlled manner (emergency deceleration). Around 100-250 milliseconds later, all power is removed from the motors and the mechanical brakes are activated. This second signal is purely implemented in hardware (time-delayed relay and power circuit breakers). So if the software is not responding, it still shuts down the system (delayed by a split second), but in the normal use case, it shuts down the system fast and gentle (slamming the mechanical brakes in full speed would destroy them after just a few tries).
I would love to see that in tinyg V9, but it requires additional hardware (inputs for emergency stop and re-enable, AND-gate for all motor + spindle enable signals) and software.
And it could possibly raise liability issues (I guess that's the reason why there is no emergency stop handling in current tinyg, thus the responsibility is shifted to the user).
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