If you are using an ACORN 3, the ALARM (drive fault signal) from the DYN4 is a pulsed signal. It is NOT high it is NOT low, and will not trigger the ACORN 3 input.
Hi Marty, please post when you get a answer on the alarm question , i see that Reedfirst posted about using a Mosfet to correct the problem .
Does this include the limit Zero function as well for homing .
The Opto circuit has been deleted, because there are some components and values that may not work well long term as pointed out by Centroid Engineering. More updates will be provided once they are tested and permanent, anything else at this point is an experiment.
Last edited by martyscncgarage on Mon Jan 29, 2018 3:34 pm, edited 4 times in total.
Reminder, for support please follow this post: viewtopic.php?f=20&t=383
We can't "SEE" what you see...
Mesa, AZ
spindle Nerd wrote: ↑Fri Jan 26, 2018 9:07 pm
How to determine what model of Acorn you have? and this is really starting to get weird with all this DMM tech stuff.
Revision 170630 and newer have updated input circuitry for the screw terminals to improve noise immunity. The revision is printed on the board near the second step and direction header (H3). The revision is a date (YYMMDD).
ACORN v2 / v3 represent major firmware changes. It is not accurate to describe the hardware / PCB changes as v2 or v3. There are 5 revisions of the ACORN PCB.
spindle Nerd wrote: ↑Fri Jan 26, 2018 9:07 pm
How to determine what model of Acorn you have? and this is really starting to get weird with all this DMM tech stuff.
Revision 170630 and newer have updated input circuitry for the screw terminals to improve noise immunity. The revision is printed on the board near the second step and direction header (H3). The revision is a date (YYMMDD).
ACORN v2 / v3 represent major firmware changes. It is not accurate to describe the hardware / PCB changes as v2 or v3. There are 5 revisions of the ACORN PCB.
Could you elaborate on this?
I know the db 25 pins are now programmable.
The screw terminals can now be unplugged from the board.
Apparently there is updated circuitry for better noise immunity.
Not all revisions were generally available.
160520 First revision
160830 Spindle encoder added, other minor improvements
170630 Improved opto input circuit, diode to prevent feedback from DB25 inputs, circuits to help BeagleBone startup reliability, other minor improvements
170918 push-pull logic outputs for DB25, removable headers, NC relay terminals on headers, DB25 remapping (v3 firmware)
171025 power LED added, PCB routing fixes, silk screen fixes
When the DYN4 has an alarm, the signal goes high for 400ms, then low for 400ms (a square wave).
There is a filter in the PLC program to ignore false alarms with some drive brands. Parameter 991 is the filter time in ms, and is 1000 by default. Set parameter 991 to 1 to recognize the DYN4 alarm.
The ACORN input filter is under 250us, so the board revision is not related to this issue.
When the DYN4 has an alarm, the signal goes high for 400ms, then low for 400ms (a square wave).
There is a filter in the PLC program to ignore false alarms with some drive brands. Parameter 991 is the filter time in ms, and is 1000 by default. Set parameter 991 to 1 to recognize the DYN4 alarm.
The ACORN input filter is under 250us, so the board revision is not related to this issue.
Soo! do we need to build the board Marty came up with or just change this parameter ?
When the DYN4 has an alarm, the signal goes high for 400ms, then low for 400ms (a square wave).
There is a filter in the PLC program to ignore false alarms with some drive brands. Parameter 991 is the filter time in ms, and is 1000 by default. Set parameter 991 to 1 to recognize the DYN4 alarm.
The ACORN input filter is under 250us, so the board revision is not related to this issue.
Soo! do we need to build the board Marty came up with or just change this parameter ?
The Board Marty Built (nice solution by the way) and the MOSFET I used (just different ways of doing it) is for using the Z+ encoder output from the DYN4 drives to interface with the Acorns inputs. This is for accurate homing of the machine.
I"m about to walk out to my machine, change the parameter as per eng199 and report back if the alarm starts working.