[SwampDonkey]

When I powered my machine yesterday up none of the lights on the stepper drivers came on are they all dead? I checked wiring, all are getting around 75V, no fuses burned. Im at a loss.

Thanks in advance,

SD

[cgo]

just replied to your other thread for the same problem, hard to tell from so little information, maybe more details of what your using and maybe a picture or other info would help.

[SwampDonkey]

Sure thing. I was boring a hole in piece of cast iron when the Z axis dropped - under power. It was odd so I shut down and checked out the wiring and made sure the brake/ stepper/ ribbon cable was all in place. It was. So I played with it a bit and jogged the axis to make sure everything was working as it should- figured it must have been an issue on the computer end. Every stepper driver went dark. Just suddenly the green lights went out.
Checked the BUS to make sure everything was getting power, it was. Checked, rechecked, still checking. Every wire, every connection. Nothing. Not even a blown fuse.

Attachment 242574




The power is on in this photo. stuff is moved around from me trying to troubleshoot the issue. This is frustrating. Ive had this mill for almost a year, upgraded EVERYTHING to series 3 hardware and its failed every time ive tried to use it. Every single time. So much money.......

[cgo]

I would suspect the board with all the fuses has a problem, cant see all the drives going bad at the same time. This is your common connection between all the drivers.
Plus each driver is fused from that board so if one went bad (chances are when it does it will go shorted and not open) so that drivers fuse would pop.

I would test for voltage at each drive (both test leads) and not at the fuse board (you may have done that ?)

Any crimp connection can be a problem point if the crimp doesnt match the wire size or not crimped right. Ive ran into this problem several times.
Testing for this would need to be done with power on, a careful and slow process of checking for voltages at each driver at the farthest most connection point you can get to.

It could be the "plug-screw terminals" at the driver itself that are losing power, or even where there soldered to the board, a wiggle of the plug or light tapping with the handle end of a screw driver could find this problem.(this would be a single drive not all of them)

The driver lights should be powered by the 75 volt side and not the bob side but I dont have the schematic for those drivers to check it.
It says the driver will go into shutdown at 91 volts but the red light will be on, not the problem since the parts are rated for at least double what they run at anyway (24-80vdc).
Also says if you hook it up reverse polarity it will damage it, I would bet it would be a dead short if you did this, popping a fuse.

[SwampDonkey]

I would suspect the board with all the fuses has a problem, cant see all the drives going bad at the same time. This is your common connection between all the drivers.
Plus each driver is fused from that board so if one went bad (chances are when it does it will go shorted and not open) so that drivers fuse would pop.

I would test for voltage at each drive (both test leads) and not at the fuse board (you may have done that ?)

Any crimp connection can be a problem point if the crimp doesnt match the wire size or not crimped right. Ive ran into this problem several times.
Testing for this would need to be done with power on, a careful and slow process of checking for voltages at each driver at the farthest most connection point you can get to.

It could be the "plug-screw terminals" at the driver itself that are losing power, or even where there soldered to the board, a wiggle of the plug or light tapping with the handle end of a screw driver could find this problem.(this would be a single drive not all of them)

The driver lights should be powered by the 75 volt side and not the bob side but I dont have the schematic for those drivers to check it.
It says the driver will go into shutdown at 91 volts but the red light will be on, not the problem since the parts are rated for at least double what they run at anyway (24-80vdc).
Also says if you hook it up reverse polarity it will damage it, I would bet it would be a dead short if you did this, popping a fuse.

Yeah You're thinking the same thing I did. All fuses are fine, all voltages are around 75V right at the driver pins, they're definitely getting power. I checked wires and connectors for 2 days. Nothing I can find would cause this. I'd like to find another machine to try a driver on and see if its just my cursed 1100.

[cgo]

Besides losing a connection inside the driver itself , which would require you to remove the cover and inspect the boards for bad solder connections or a fusable link.

The only other thing I could see is either a bad power supply filter cap (the big cap) or bad connections to it, but that would mean that all the drives are bad also from too much ripple in the dc voltage, based on what you have described so far. This would show up under high loads and may not be noticeable at first since each driver has its own filter caps but there not large enough to cover the power supply ripple at full load, mostly for noise reduction.

[SwampDonkey]

Besides losing a connection inside the driver itself , which would require you to remove the cover and inspect the boards for bad solder connections or a fusable link.

The only other thing I could see is either a bad power supply filter cap (the big cap) or bad connections to it, but that would mean that all the drives are bad also from too much ripple in the dc voltage, based on what you have described so far. This would show up under high loads and may not be noticeable at first since each driver has its own filter caps but there not large enough to cover the power supply ripple at full load, mostly for noise reduction.

You probably have something there. That cap is the only original piece of Tormach electronics from 2007 when the machine was built. It was probably rippling the hell out of the current going to my drivers. This explains alot of erratic behavior in the past. I think you nailed it bud. Now....did I kill my drivers and out the hundreds of dollars to replace them?

[cgo]

The drivers typically go shorted when they go, internally they may have a fuse/fusable link but it should be last to go.
Maybe time to remove a cover and inspect one, ripple could cause heating and open a solder connection.

If you noticed it acting up under heavy loads or rapid speed changes more than jogging or other light duty tasks then I would suspect the cap. It does work very hard and is the weak link in a linear supply, over time.

[SwampDonkey]

Its funny you mention that because when my first driver died I suspected a fuse. I was right. I replaced the fuse and kept it as a spare since I already ordered a new one. The machine always acted oddly. Im on my second board, which seemed to help a bit for a while. Anyway, I wrote to Greg and informed him about the filter cap being the likely destroyer of my bank account and many Tormach electronics. Im kind of shocked nobody mentioned it when I was calling every day with problems (check out my post history). The new cap is a beast compared to what I have:

OLD CAPACITOR

NEW CAPACITOR

The drivers typically go shorted when they go, internally they may have a fuse/fusable link but it should be last to go.
Maybe time to remove a cover and inspect one, ripple could cause heating and open a solder connection.

If you noticed it acting up under heavy loads or rapid speed changes more than jogging or other light duty tasks then I would suspect the cap. It does work very hard and is the weak link in a linear supply, over time.

[cgo]

Different brand too, new unused caps can go bad sitting on the self btw.
Its rating is at what you said your reading was, from my experience a voltmeter may read a little high when a power supply has ripple (bad cap).
Could measure the ac side of the bridge on the fuse board to find your rms voltage.

If the power supply really runs that cap at its max voltage rating all the time its probably going to go bad or get hot, usually you leave a little headroom for voltage fluctuations.
They must be unloading those new caps as fast as they can for $8 and the old one is only 85c temp , 105c is the good stuff.
Cant see the rating on there new cap.

[SwampDonkey]

Yeah I just checked it, 78.6V after starting it up and waiting a sec. If this destroyed all my expensive stuff and I just get stuck with it Im going to be...disappointed. Then throw things.

Different brand too, new unused caps can go bad sitting on the self btw.
Its rating is at what you said your reading was, from my experience a voltmeter may read a little high when a power supply has ripple (bad cap).
Could measure the ac side of the bridge on the fuse board to find your rms voltage.

If the power supply really runs that cap at its max voltage rating all the time its probably going to go bad or get hot, usually you leave a little headroom for voltage fluctuations.
They must be unloading those new caps as fast as they can for $8 and the old one is only 85c temp , 105c is the good stuff.
Cant see the rating on there new cap.

[cgo]

Heres the 105c caps in stock value and a little higher capacitance.
LNT1K153MSE Nichicon | 493-8970-ND | DigiKey

LNT1K223MSE Nichicon | 493-8971-ND | DigiKey

If you have to get new drives , I would goto leadshine directly maybe or inquire with them about the problem too.
http://www.leadshine.com/UploadFile/Down/3ND883m.pdf

[SCzEngrgGroup]

---This would show up under high loads ...

Steppers have no concept of "high load". Unlike a AC and DC motors, stepper motors run maximum current whether heavily loaded or not.

Regards,
Ray L.

[cgo]

That was regarding 3 phase hybrid steppers and drives.
Even looking at my regular steppers with an amp probe just now they also draw more running than holding, and even more power switching directions such as running complex code.

[TurboStep]

I too find it strange that all 3 stopped working at the same time. I took one of my drives apart a few weeks back but I can't remember whether it had an internal fuse - didn't take any photos either, but it's easy to just remove the cover to check for damage. if power electronics fry (I don't mean fuses) it usually smells burnt - can you smell anything?
These don't appear to be standard Leadshine units but I would hope they still have over-voltage protection. In which case they should turn off when something over 90V is exceeded and then I would expect them to withstand quite a bit more (for a limited time of course). If they were tripping due to ripple peaks then the red LEDs should probably be illuminated anyway. From your photo this doesn't look to be the case.
What happens if you turn off the power until the supply drops to, say below 10V, and then turn on again. Do the LEDs blink once or don't they light at all?

For the record, my power supply runs at about 65V so either yours is somehow configured to deliver more than mine or there is little or no load.
Good luck
Step

[SwampDonkey]

They typically stayed green except during startup, but this was not entirely consistent. A few times I would get a flash of red as the machine comes to life. Typically the door is shut and I cant see what they're doing though. Also, its not like I can use the thing. Its had weird issues from the day I got it.

I emailed Greg at Tormach to see what their attitude towards this is. If I cant get them to replace the drivers and cap, I gotta find a way to sell a broken mill.

I too find it strange that all 3 stopped working at the same time. I took one of my drives apart a few weeks back but I can't remember whether it had an internal fuse - didn't take any photos either, but it's easy to just remove the cover to check for damage. if power electronics fry (I don't mean fuses) it usually smells burnt - can you smell anything?
These don't appear to be standard Leadshine units but I would hope they still have over-voltage protection. In which case they should turn off when something over 90V is exceeded and then I would expect them to withstand quite a bit more (for a limited time of course). If they were tripping due to ripple peaks then the red LEDs should probably be illuminated anyway. From your photo this doesn't look to be the case.
What happens if you turn off the power until the supply drops to, say below 10V, and then turn on again. Do the LEDs blink once or don't they light at all?

For the record, my power supply runs at about 65V so either yours is somehow configured to deliver more than mine or there is little or no load.
Good luck
Step

[SwampDonkey]

Well, hell. I guess I'll give it a week to see what Tormach's response to this is then put up the new board and the steppers for sale on ebay. I only checked the fuse on one of them and thats the one that works. I have to recoup some if this loss somehow. I cant afford new steppers and a broken mill isnt worth much.

[patlandy]

Don't know anything about the machine, but I do know that the most common aliment to look for when multiple circuits are not operating and you have voltage to the units is a faulty ground.....