Acorn suddenly having issue turning on.

[Reedfirst]

So tonight I started having a weird issue with my Acorn powering on.

I have the power supply for the acorn connected to a relay. When the relay is energized it supplies the power supply with 120vac and the power supply turns on as it should. The green light comes on and there is 24vdc reaching the acorn board. Checked with my DVM. The Acorn however doesn't turn on.

The weird issue is, if I disconnect the +24vdc from the acorn board and instantly reconnect it again, the Acorn powers up and works just fine. It connects to my pc, and I can control my machine once again.

If I power down the relay which turns off the power supply and turn it back on again, the acorn won't power up unless I disconnect the +24vdc and reconnect it again.

I am hoping this is just a power supply issue.

[martyscncgarage]

So tonight I started having a weird issue with my Acorn powering on.

I have the power supply for the acorn connected to a relay. When the relay is energized it supplies the power supply with 120vac and the power supply turns on as it should. The green light comes on and there is 24vdc reaching the acorn board. Checked with my DVM. The Acorn however doesn't turn on.

The weird issue is, if I disconnect the +24vdc from the acorn board and instantly reconnect it again, the Acorn powers up and works just fine. It connects to my pc, and I can control my machine once again.

If I power down the relay which turns off the power supply and turn it back on again, the acorn won't power up unless I disconnect the +24vdc and reconnect it again.

I am hoping this is just a power supply issue.

Have you changed ANYTHING?
Are there any other power supplies involved?
ALL LED's out on ACORN or?
When Acorn does not come on, did you check for 24VDC AT Acorn Terminals before powering down and restarting?
Do you have a wiring schematic done you can share?
Be sure to upload a report....

Marty

[Reedfirst]

Didn't change anything since it was working.

Same power supply powering acorn since day 1

I did add a 5 volt power suppply but that's connected to the dyn4 drives.

No lights on the acorn at all.

Power is at the acorn (+24vdc) and power supply is on when the acorn doesn't come on.

If I disconnect the +24vdc while leaving the power supply on and reconnect it again the acorn powers up and works fine.

I'll get a report up soon if it'll help. but once it turns on it works fine.

[martyscncgarage]

Didn't change anything since it was working.

Same power supply powering acorn since day 1

I did add a 5 volt power suppply but that's connected to the dyn4 drives.

No lights on the acorn at all.

Power is at the acorn (+24vdc) and power supply is on when the acorn doesn't come on.

If I disconnect the +24vdc while leaving the power supply on and reconnect it again the acorn powers up and works fine.

I'll get a report up soon if it'll help. but once it turns on it works fine.

The Beaglebone Green has some safety features that prevent it from turning on. That's why I asked.

How long has this been happening? How long has it been working normally with no changes to wiring?

Do check for 24VDC at Acorn next time it doesn't come up.

Try this at your own risk. (Should be NO issue with pressing it really)
There is a POWER button on BBG, its right next to the Ethernet port.
Push it next time it doesn't come up and see if it powers up.
Marty

[martyscncgarage]

Didn't change anything since it was working.

Same power supply powering acorn since day 1

I did add a 5 volt power suppply but that's connected to the dyn4 drives.

No lights on the acorn at all.

Power is at the acorn (+24vdc) and power supply is on when the acorn doesn't come on.

If I disconnect the +24vdc while leaving the power supply on and reconnect it again the acorn powers up and works fine.

I'll get a report up soon if it'll help. but once it turns on it works fine.

Did you use a Meanwell dual output power supply or is your 24VDC power supply and 5VDC power supply separate?
I think there have been issues using 2 separate power supplies and the 5VDC beating the 24VDC on power up causing the symptoms you describe. Beagle bone's protection features seem to prevent it from starting up. Just an idea. Because of this, I stick to using one power supply with dual outputs when needed just to be sure.
Marty

[andyolney]

I'm having the same problem. A thread that I can't find at the moment mentioned having this problem and their fix had something to do with the 5 volt power. I removed my five volt power from my dual power supply and the beaglebone booted fine. Replaced the 5-volt and it still boots fine. Go figure.

Andy

[Gary Campbell]

Andy...
I solved the issue on my board by running the 5volt power thru an output/relay to OKFault. More info and my hacked schematic near the end of this thread: viewtopic.php?f=60&t=1395&p=8266#p8266

[Reedfirst]

Ok, so I was outside doing some tests and figured out the problem has to do with the 5 volt power supply going to the dyn4 drives. I

I still haven't figured out exactly what is causing the problem so I'll just list my findings here until I can do more testing.

1. If I disconnect the +5volt power supply the Acorn powers up as it should. One thing I did noticed is that with the +5volt supply connected and supplying power to the DYN4 drives, there is about 6 or so volts at the step and dir inputs on the acorn board.

2. Without the +5 volt power supply I get no motion from my servo motors.

3. I can reconnect the +5volt power supply and Motion resumes as normal.

4. I decided to try a different +5volt power supply and oddly enough, while connected, the Acorn powers up fine and motion control works normally. HOWEVER, upon tuning everything off, I experienced a sudden servo "jump" of about 1/4 turn on all axes. Marty, I think you are experiencing this too?


It seems that the different characteristics of the two power supplies are causing different reactions with the Acorn Controller. I am leaning towards a timing issue (power supply ramp on and off times) that are causing my problems.

I plan to do some more testing with my o-scope and see if I can come up with some for info...

[Reedfirst]

Andy...
I solved the issue on my board by running the 5volt power thru an output/relay to OKFault. More info and my hacked schematic near the end of this thread: viewtopic.php?f=60&t=1395&p=8266#p8266

Looks like we're on the right track!

[Reedfirst]

Did you use a Meanwell dual output power supply or is your 24VDC power supply and 5VDC power supply separate?
I think there have been issues using 2 separate power supplies and the 5VDC beating the 24VDC on power up causing the symptoms you describe. Beagle bone's protection features seem to prevent it from starting up. Just an idea. Because of this, I stick to using one power supply with dual outputs when needed just to be sure.
Marty

My Power supplies are separate. When Centroid updated the wiring schematic for the DYN4 drives the showed a separate power supply so that's what I did. I went ahead and ordered a dual one as they are pretty inexpensive. I am also contemplating using the +5v output from the pc power supply that is powering my Acorn PC. Since the pc and the Meanwell power supply share the same ground it should be no problem. But at this point, I'm checking everything to figure out what's exactly going on.