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General Mach Discussion / Re: Are these servo/steppers appropriate for mach3 ? (Fastech EZI-Servo)
« on: October 01, 2010, 10:32:40 PM »
Hello Hood,
Those are some powerful motors for CNC if I'm not mistaken !
We use 18 N.m motors at work to move tonnage up and down, counterweighted yes, but running at 2m/s or so she picks up a fair bit of momentum
There are large safety factors involved in what I do also
In the meantime I'm learning slowly what I need and come up with a slightly better specification:
************
I have two applications that I'd like to purchase motion control gear for - I'd like to try to get gear that can be used in both applications (there maybe a little adaptation involved in one or more of the cases):
First application:
A 4 axis mill/drill CNC conversion using EMC2 as the controller (the 'loop') or mach3 if that proves troublesome
Second application:
A generic 4 axis machine in which the purchased drives can handle being fed simple step/dir pulses (from an arbitrary source) with the drives doing their own PID control internally (no more PC attached!)
Consequences I've discovered that will likely need addressing:
-I will likely need some sort of USB or parallel I/O card to free me up of on board parallel port restrictions in EMC2 (I'd prefer not PCI bus) - Mesa gear looks interesting here as it is EMC2 ready
-Once the above point is taken care of its looks like I can have high resolution (incremental) encoders - I'd like them for obvious reasons
-The motor drives would be good if they were able to be hijacked or switched to allow the encoders to go to EMC2 directly (or indirectly) for the CNC, the motors would then run 'dumb'. (If this is impossible within the spec I give then I can run EMC2 (or mach3) open loop with the drive running the loop.)
-Assuming the last factor can be addressed I need ALSO to be able to split the encoder stream for the second application, one stream to the drive for its internal PID loop again ('smart' mode), the other split to the arbitrary 'brain' for other purposes (non real time, non control).
Limiting factors:
-I'd prefer brushless servos for the motor, but standard servos are fine also
-COST - I'd like as high torque as I can get (NEMA34 likely?) but don't want to be spending more than around $600~$700 per axis - factor in eventual power supply cost into this also
-I live in single phase 230-240V/50Hz land - thats 10A per circuit ... 2400W max available per circuit
Notes:
I would emphasis the ability to function relatively unhindered or adapted under the second application as more pertinent than the EMC2 CNC application - that can run adapted/converted if need be...
The motors will probably be over spec for the CNC application, excess torque however will be used in the second application.
**************
Any thoughts ?
Those are some powerful motors for CNC if I'm not mistaken !
We use 18 N.m motors at work to move tonnage up and down, counterweighted yes, but running at 2m/s or so she picks up a fair bit of momentum
There are large safety factors involved in what I do alsoIn the meantime I'm learning slowly what I need and come up with a slightly better specification:
************
I have two applications that I'd like to purchase motion control gear for - I'd like to try to get gear that can be used in both applications (there maybe a little adaptation involved in one or more of the cases):
First application:
A 4 axis mill/drill CNC conversion using EMC2 as the controller (the 'loop') or mach3 if that proves troublesome
Second application:
A generic 4 axis machine in which the purchased drives can handle being fed simple step/dir pulses (from an arbitrary source) with the drives doing their own PID control internally (no more PC attached!)
Consequences I've discovered that will likely need addressing:
-I will likely need some sort of USB or parallel I/O card to free me up of on board parallel port restrictions in EMC2 (I'd prefer not PCI bus) - Mesa gear looks interesting here as it is EMC2 ready
-Once the above point is taken care of its looks like I can have high resolution (incremental) encoders - I'd like them for obvious reasons
-The motor drives would be good if they were able to be hijacked or switched to allow the encoders to go to EMC2 directly (or indirectly) for the CNC, the motors would then run 'dumb'. (If this is impossible within the spec I give then I can run EMC2 (or mach3) open loop with the drive running the loop.)
-Assuming the last factor can be addressed I need ALSO to be able to split the encoder stream for the second application, one stream to the drive for its internal PID loop again ('smart' mode), the other split to the arbitrary 'brain' for other purposes (non real time, non control).
Limiting factors:
-I'd prefer brushless servos for the motor, but standard servos are fine also
-COST - I'd like as high torque as I can get (NEMA34 likely?) but don't want to be spending more than around $600~$700 per axis - factor in eventual power supply cost into this also
-I live in single phase 230-240V/50Hz land - thats 10A per circuit ... 2400W max available per circuit
Notes:
I would emphasis the ability to function relatively unhindered or adapted under the second application as more pertinent than the EMC2 CNC application - that can run adapted/converted if need be...
The motors will probably be over spec for the CNC application, excess torque however will be used in the second application.
**************
Any thoughts ?
