New build with recycled parts on a ridiculous budget 120cm*60cm work area

[Neale]

Short answer - no!

Longer answer - the AM882 use an open-collector output. Think of it as being a normally-open switch that closes when there is a fault (like a stall). What you can do is wire them all in parallel and then to the BOB input. I do this with the EM806 on my machine and it works fine.

[Desertboy]

A little bit closer, ready to mount the box and start running the motor's and home switches. Need to mount the VFD as well so I can run the wiring 12v adapter won't be here till Monday.

Need holesaw for the fans mate has my cheapo set so going to see him tonight little bastard keeps forgetting it.

[Desertboy]

Does this look correct it's the pulse and dir +'s connected to BOB pc 5v

[m_c]

Short answer - no!

Longer answer - the AM882 use an open-collector output. Think of it as being a normally-open switch that closes when there is a fault (like a stall). What you can do is wire them all in parallel and then to the BOB input. I do this with the EM806 on my machine and it works fine.

I'm not sure about the AM882s, but with the software you can configure the EM806 so the fault output is active when ok (i.e. switched on), and goes inactive on fault (i.e. open circuit). That's how I configured my EM drives, which would allow you to loop through all the fault outputs and create a failsafe circuit.

[Neale]

I'm not sure about the AM882s, but with the software you can configure the EM806 so the fault output is active when ok (i.e. switched on), and goes inactive on fault (i.e. open circuit). That's how I configured my EM drives, which would allow you to loop through all the fault outputs and create a failsafe circuit.

You are probably right about the AM882 also being software-configurable, but it looks as if getting a cable to be able to reprogramme the 882 and making all the configuration software work is another can of worms (judging by the experience of other people). I know it shouldn't be, but I didn't need to use the fine-tune facilities available through software and could manage with just the DIP switch options, so I chose not to change the factory setting for the alarm. That way I avoided any need to play with the configuration software. My thinking in this case was that normally you would be a bit more paranoid about NC connections, but here all the connections are hard-wired inside the box and so rather more reliable than anything going via plugs and sockets and around the machine itself.

Your recommendation is the better one; I chose to use a very slightly inferior option, and one that would be easier for the OP to use. Connecting in the fault outputs at all is a big leap forwards!

[Clive S]

For the avoidance of doubt I use AM882's on the router, they are programmable with the RJ11 socket on the end.

You can make a lead up from an old phone then chop the end off and fit a D9 plug on using just 3 wires. Then use a USB to D9 adaptor to connect the RJ11 lead to the PC.

[Desertboy]

I need to work hardwoods with the machine, Predominately Oak, Walnut and Mahogany. I'm hoping it's strong enough.

I am planning to swap the gantry over to shortest span (Unless I have 0 issues with flex in which case I will keep it this way as it makes loading the router easier.). Originally I was going to have SBR25 on the bottom which is why I made the gantry the longest span with the hiwin's but since that has changed to Hiwin's all round I need to buy another ballscrew 1400mmm to swap it over.

I thought though it'd be best to use it for a bit to decide if when I do buy a new ballscrew if I should just change all 3 ballscrews to 1610's instead and upgrade the 2nm nema's to 3nm ones at the same time.

I've also been toying with when I swap the gantry over buying another set of 1500mm 15mm clone hiwins and having 2 rails per side on the bottom axis. Then making new plates all round and increasing the Z travel to 35cm! This would mean some serious rebuilding which I wonder if it's worth it at some point in makes more sense to build a new steel framed router then upgrade the old aluminium one.

[Desertboy]

I'm not sure about the AM882s, but with the software you can configure the EM806 so the fault output is active when ok (i.e. switched on), and goes inactive on fault (i.e. open circuit). That's how I configured my EM drives, which would allow you to loop through all the fault outputs and create a failsafe circuit.

I never understood what you wrote the first time but rereading it now it makes a lot sense basically setting the fault output to Normally Open. Basically doing the same as with microswitches setting them NC so if there's a dodgy connection line it will fault.

This is from the AM882 manual not got mine connected yet did make a cable but lost it lol but have more donor cables and usb to rs232 for the job.


I wonder if the AM882 software works with Wine if it does I could use the linuxcnc to talk to the drivers which would be convenient but it's nto a major hassle to drag a windows laptop to the drivers for tuning.

Alarm signal high/low will be it and also interesting I can inverse the AM882 direction in software although I can imagine annoying later down the line when you forgot what you did and are reusing the drivers lol.

I'm running the stall to the Estop so will need to swap the wiring round on the emergency stop button to NC to match and invert the Estop pin but no biggie.

[phill05]

Short answer - no!

I do this with the EM806 on my machine and it works fine.

Sorry to jump in on this thread Neale would the wires from the EM806's go to the E stop on the BOB?

[Desertboy]

Sorry to jump in on this thread Neale would the wires from the EM806's go to the E stop on the BOB?

That's how I have it setup the black cables are the stall protection


Powered on today ;) can't test it because I took the Z axis plate off and it's still with engineering firm although ready to collect Monday.