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Re: Dyn4 to Acorn cable - Why not utilize the Dyn4’s internal 5v power supply ?

Posted: Mon Feb 11, 2019 6:30 pm
by slodat
DMM sent me a different pdf file this morning with their instructions for connecting to Acorn.

Re: Dyn4 to Acorn cable - Why not utilize the Dyn4’s internal 5v power supply ?

Posted: Mon Feb 11, 2019 8:00 pm
by cut2cut
slodat wrote: Mon Feb 11, 2019 6:30 pm DMM sent me a different pdf file this morning with their instructions for connecting to Acorn.
DMM sent me one too. Is it this one ? It has multiple errors ( 2000 in gear num is the proper number and Servo Enable should be set to High ( unchecked ).

[ 2nd Edit , I found a second error. Servo Enable should be set to "HIGH" ( unchecked ) ( NOT LOW as pictured ) .....This must have been an early draft that DMM gave me by accident !!! ]

Jake

Re: Dyn4 to Acorn cable - Why not utilize the Dyn4’s internal 5v power supply ?

Posted: Mon Feb 11, 2019 8:16 pm
by martyscncgarage
I covered all this in an Acorn-Dyn4 setup.
Short answer is yes. 2000 gear number
In Acorn, set the Steps/Rev to 8000

https://youtu.be/TFCWAxQkxok

The Centroid Schematic is correct. It uses 5VDC logic rather than the 2k resistor in the DMM cable which reduces the voltage to 5VDC.
The DMM Schematic works with their cable.

Marty

Re: Dyn4 to Acorn cable - Why not utilize the Dyn4’s internal 5v power supply ?

Posted: Wed Feb 13, 2019 5:36 pm
by oscilloman
The first schematics from Centroid for wiring DYN4 drives used DYN4's internal 5V. My machine is setup using this and it is still working 1.5yrs later :-)

Re: Dyn4 to Acorn cable - Why not utilize the Dyn4’s internal 5v power supply ?

Posted: Thu Feb 14, 2019 3:11 am
by cut2cut
oscilloman wrote: Wed Feb 13, 2019 5:36 pm The first schematics from Centroid for wiring DYN4 drives used DYN4's internal 5V. My machine is setup using this and it is still working 1.5yrs later :-)
Cool, thank you, it totally seemed like a waste to not use the Dyn4's internal 5vdc power supply. It would free up a wire too, for things like a Z axis servo brake ( to stop the Z axis from free falling when not powered / enabled. ) Using a cat 7 cable with 4 pairs of twisted wire and foil shields and a braided shield should not suffer from noise however, it seems the DYN4 doesn't have "standard" grounded DB 9 and DB25 connectors. My motors ( like another fellows recently ) were jittering around ***UNTIL**** I ran a jumper from the Dyn4 ground screw to the nut on the DB9 connector ( using the nut on the DB25 connector is the same as they are on the same metal plate. ( note, It only happened ( motor jittering around uncommanded ) when I had two drives powered up simultaneously ). Basically, in the cable I made, I connected the Cat7 cable shielding to the male DB25 connector but since the Dyn4's female DB25 connector ( and DB9 ) aren't grounded at all the shield was not connected to ground and wasn't functioning as a shield at all.

Credit goes to Jerry / Fozzybear for figuring out that the DYN4's DB25 and DB9 's aren't grounded !

Cheers !

Jake