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I have 2 open loop nema 34 motors driving my y axis. They each use a Dma860h controller. The motors are 34hst9805.
Can anyone recommend a controller that has error checking? I would prefer for the machine to shut down if there is a problem but because these are open loop there is no fail safe. Makes me nervous.
Thanks.
You need closed loop drivers and motors for that.Quote:
Originally Posted by grantx
Not possible with open loop.
If your motors are dual shaft you could fit encoders and get new drives but personally I would ditch Nema 34 size and drop down to 24 size motors while you're at it.
They'll be a lot quieter.
I've noticed you are on mycncuk and it lists ayou as in uk.
If that's so.... Shoot Dean (Jazzcnc) a msg on there about the Lichuan LCH2102's and LCD86's
But.......... If you are a serious machiner and do a lot of stuff....... Go for servo's with A2 / A4 drives
Hi. Yeah I'm in the UK. I have already spoken to Dean and he has been quite helpful. My question is, if put closed loop drives and motors on the y axis will that eliminate the chance of the gantry twisting? Ie, do the controllers monitor each others position?
Quote:
Originally Posted by dazp1976
TBH I don't know much on closed loop systems.Quote:
Originally Posted by grantx
However. I assume that if you tie in all the alarm and enable signals (either parallel or series depending on switching position) they will all shut down together and prevent twisting to a large degree.
That's my take on it anyway. Likely you'll still have to double check it afterwards.
Yeah I will wire into the emergency stop circuit so the whole thing shuts down if there's a problem.
What cnc do you have?
Quote:
Originally Posted by dazp1976
Just a 3 axis mill conversion for now. Amadeal AMAT25LV.Quote:
Originally Posted by grantx
Doing an electronics upgrade atm to a UC300eth, UCBB, bigger drivers, and putting a 1.8kw servo on the spindle.
Been gradually putting the machine together for a while.
Should've had it finished ages ago but things happen.
There's a lot of people out there that don't bother with things like the enable, as drivers are enabled by default. Relying on software shutoff.
I always wire mine in, tie it into a relay, and hook it up into the estop.
That way you have both a software and a hardware safety circuit.
If you use this kind of closed-loop stepper Motor, it has alarm output
https://www.automationtechnologiesin...op-stepper-kit
I wouldn't mind upgrading to the AXBB-E. I will at some stage in the near future, then I don't have to do the whole USB thing.
I understand that the UCCNC software is also very good.
Why would you switch through a relay? There is no load is there?
Depends how you have it set up.Quote:
Originally Posted by grantx
My estop circuit is 24v set as active high (I think) normally closed circuit. When there is 24v present the machine is 'ready', when it's 0v the estop is active.
My enable circuit is on 5v (when the 0v of this is signalled the drivers disable) so I can't just simply splice it and the stop circuit together.
Using Linuxcnc if your drives have an error output, you can connect them to an amplifier fault in input