- Posts: 22012
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Basic Mesa 7i76e Wiring Question
- tommylight
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The issue is with the err/reset pin on the gecko as it is an input and output at the same time, I do have some collecting dust somewhere, but I could not recalled exactly how it worked.
Here is an exempt from the g320x manual:
Quote :
Normally when the G320X is first powered up, it will be necessary to push the momentary switch to START for 1 second. This
will clear the power-on reset condition and extinguish the FAULT LED. The motor will then be enabled and the drive will begin
to operate. If at any time after that a condition occurs that causes the G320X to “FAULT out”, such as not being able to
complete a step command, the ERR/RES terminal will go to “0”, signaling to the controller an error has occurred. This will
require the operator to correct the problem that caused the FAULT and then push the switch to “START” for 1 second to re-
enable the G320X.
End quote.
That explains it, but not very useful.
Linuxcnc can be easily programmed to output a signal of any duration on any outputs automatically when out of e-stop or when drives are enabled with F2, but since that same output will be pulled to the ground by a fault on the gecko, I do not know if that would effect the output on the Mesa card if it happens while that output is still high. PCW might explain that much better than me and the implication of implementing that.
In normal use that would aslo require wiring that same pin to an input on the mesa board.
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- thefabricator03
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When they are in a fault position I have 0 VDC on the circuit,
When I reset them I apply 5 VDC to the circuit and then it stays at 5 VDC
When I want them to fault I ground the circuit to 0 VDC and it maintains 0 VDC,
So with using the encoder index on the mesa 7i76e should I not be able to wire the circuit with a common ground then when the circuit has 5 VDC applied it will be high and when 0 VDC is applied it will be low?
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1. Will the 2K pullup to +5 on the index input reset the fault?
(that is will a pullup current of 2.5 mA reset the drive)
2. Is the Gecko reset ground = motor power ground?
If so, this is not too nice as you throw away all the nice
optoisolation of the step/dir inputs.
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- tommylight
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PCW wrote: A couple unknowns
1. Will the 2K pullup to +5 on the index input reset the fault?
(that is will a pullup current of 2.5 mA reset the drive)
2. Is the Gecko reset ground = motor power ground?
If so, this is not too nice as you throw away all the nice
optoisolation of the step/dir inputs.
I will try to check that later in the evening and report back.
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- tommylight
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It is referenced to encoder supply, not to motor supply, so the isolation is OK.
Also after setting to ready mode the current draw drops from said 21.6 MA to 0, so using field outputs is possible only if Mesa is set to use 5V signalling. Using encoder pullups most probably will fail to set it properly.
Also note that this test was done using a G320 not a G320X, so there might be differences.
PCW, what are the implications of using one of the following :
Field output through a 100 Ohm resistor to gecko and from gecko to the index input. Since the output should be on for 1 second or thereabout, would it be to much draw ?
5V encoder power through 100 Ohm resistor to spindle enable and from enable to gecko, from gecko to spindle index input ?
That current draw will be repeated on every enable, and during wiring and testing that happens very often.
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but you need a stiff pullup to 5V to reset a fault (pushbutton?, relay, opto etc)
The 7I76 spindle optos are free if not used for a plasma setup so should work
(they are Darlington type and will actually supply about 100 mA)
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- thefabricator03
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I have returned the Gecko drives for a full refund and brought Leadshine servo drives that have a normal fault output signal.
Anyone reading DONT BUY GECKO G320X SERVO DRIVES, unless you want to stuff around with something that should be straight forward and you have a lot of patience.
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thefabricator03 wrote: Finally solved the Gecko servo drive error/reset problem,
I have returned the Gecko drives for a full refund and brought Leadshine servo drives that have a normal fault output signal.
Anyone reading DONT BUY GECKO G320X SERVO DRIVES, unless you want to stuff around with something that should be straight forward and you have a lot of patience.
Yes, I've always wondered why people think they are so good when all I read are problems. Granted the G251x is a nice compact form factor but really did not perform any better than my Longs Motor DM542a's. I accidentally fried the Gecko and tried real hard once to do the same on the Chinese one but I simply could not kill it!
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The relay outputs are tied to the "joint.n.amp-fault-in" pin for each axis.
I use the rising and falling edge of "motion-is-enabled" to trigger the 5v enable pulse or the 0v disable pulse.
When motion is enabled it fires a momentary 5v signal to the drives and it sets a memory bit.
The memory bit starts a timer that enables 24v to the common terminal on your fault relays at completion of the enable pulse. That allows the drives to enable before EMC2 senses voltage on the fault pins.
When "motion-is-enabled" changes to false, the falling edge triggers the momentary 0v disable signal and resets the memory bit.
In the event of a drive fault or encoder failure(G320X) all drives are disabled and the notification is on screen.
All three timers only need to be a second long.
You can use one output and relay for the enable pulse if you use diodes. The disable pulse needs one output to three relays to keep them isolated.
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