What the heck am I doing wrong?

[HereinCS]

My machine is doing the march of death and overheating again....

This is what happened that cause my machine to overheat last night, now it's doing it again.

I'm trying to calibrate the steps per unit. Using metric scales. I entered 0.1 and it moved 100mm for all the axis. I thought that was fine. So I loaded in some sample gcode....and the machine just makes very small, slow clicks with barely any detectable movement....all the while the motors get glowing hot. I stopped it before my motors fry again.

What am I doing wrong here?

[ger21]

Too much current, or too much voltage going to the motors.

[microcarve]

Did you double-triple check your resistors with a meter?

Sounds like too much current. Motors do get hot, but
they should only get to about 180F max. I use this thing
from Harbor Freight to check my motor temp on all my machines.

Non-Contact Pocket Thermometer

I also do it half-fast backwards. I adjust my current down until my
motors run at a peace-of-mind approx 150F.

I've seen problems from motors running at full bore current.
And been burned by a few....

$0.02


John

[CarveOne]

I feel your pain, but can only say that once you find the problem and fix it, it will seem that it should have been obvious. Works that way for me most times. I have a new G540 with 380 oz-in motors and 48v PSU connected together with no cables other than the motor pigtails and it doesn't do this. It's driven with Mach3 also. I haven't seen anyone mention having this problem other than you. Something is seriously wrong somewhere, but I don't have a clue for you. The little driver circuits in the G540 are G251 and are supposed to be the same as in the G203V drives except for having less current output capability. It also has over-current protection (I think). They should not be supplying more current to the motors than the motors can handle. CarveOne

[HereinCS]

problem solved......my g540 just blew the z axis.... bullet proof my @#$...

[CarveOne]

Originally Posted by HereinCS problem solved......my g540 just blew the z axis.... bullet proof my @#$...

This is entirely abnormal for a G540, or any other driver for that matter. There is a serious wiring error somewhere. No electronics circuit is entirely immune to all possible external destructive errors. Even real bullets. I went through months of troubleshooting a racking problem with my G203V drives trying to slave them properly and was at the point of giving up and quitting CNC altogether. Mariss read my posts and pointed me to a voltage test to do and it led me to a wrong Mach3 setting that was causing the DIR signal logic levels to be incorrect. Not as serious as what you are experiencing, but extremely frustrating as well. Without clear photos of your control box and wiring everyone here is just guessing in the dark. CarveOne

[hemsworthlad]

Like C1 says very unusual and if it was most other drives they would have been dead long before G540.!
You obviously have either a very faulty G540 or more likely you have got some thing major wrong with either wiring or PSU sizing. If not faulty G540 then it will happen again so I would post every detail of your setup so we can help try and find any obvious errors before you try again.
Post motor model and any details of them you have also current resistors used.
Pics of control box and motor wiring will help greatly
PSU make and specs V+A.

Before the G540 expired did you try checking each motor individualy to see if they got, by individual I mean only 1 motor attached to G540. I know this is not a usual thing to do but it would eliminate a faulty motor feeding power back to the G540 but I'm clutching at straw a little now.?

Also check all wires for nicks etc that could be shorting.!

I would be very reluctant to re-attach any drive if it turns out not to be a faulty G540 untill some thing obvious shows it's head.!

regards
Dean.

[HereinCS]

I only have 3 wires going to my gecko drive. 48V dc +/- and an estop. That's not the problem. My motors are two nema17 steppers and a nema 23 stepper. I have the manufacturer's documents, confirmed the wiring and the motors did have torque. It did spin in the correct direction. I quadruple checked the resister settings and spoke with Marcus to ensure I did things right. Yet my motors still ran burning hot. I turned down the ps to 39v, still ran hot. Then the x axis light went out and nothing worked. I haven't opened up the g540 to see what's wrong, but something got cooked. There is a burn smell. I have no ideal what happened.

Spoke with geckodrive this morning. The CS rep said to just send it back and the'll fix it for free, so it's going back today.

I also ordered new nema 23 steppers from kelinginc. The nema17s I had was rated at 1.2 amp, and the nema23 that's on the machine now is rated at 2 amps. So I leave open the possibility that I'm running too much current through them. I'll report back after I hear from Marcus.

[CNC Lurker]

From the G540 manual:

Wire your motors to the included DB9 solder cup and secure the backshell connectors. If your motors are rated below 3.5A you must use a current set resistor across PIN 1 and PIN 5. The resistor is calculated by taking the current in amps and multiplying by 1000. If your motor is rated at 2.8A per phase you will have to use a 2.8K 5% 1/4W resistor. If your motor is rated at 3.5A or above you can safely not use a current set resistor; however, your G540 will not go into current standby mode which will result in increased motor heating.

In the other thread, the EZG540 was wide open: Why are my motors so hot? LINK

Not sure if that alone is the cause of the overheating, but that setting on the EZG540 was brought up in that thread.

I mention this because not having a resistor was the cause of overheating in the thread linked below. Technically the 3-axis kits in the link below did have a resistor, but since they were installed on the wrong cable end, it acted as though it didn't have a resistor:

Important Gecko 540 info - news to me!! LINK

Is your G540 under warranty?

[ger21]

Do you have the G540 heatsinked? If you were running at the max current, it's possible you overheated the G540.

[HereinCS]

I had a fan blowing at it. I was checking the temp as part of my set up, and it wasn't even warm.

Apparently I'm the only one to every blow up a g540 I have 3 g203vs sitting around, no one's ever destroyed those right?

[JC50]

Originally Posted by HereinCS I had a fan blowing at it. I was checking the temp as part of my set up, and it wasn't even warm. Apparently I'm the only one to every blow up a g540 I have 3 g203vs sitting around, no one's ever destroyed those right?

I beg your pardon, there Mr. I blew up my G540 when I built my first DIY a couple of years ago. Of course I wired the PSU backwards to the G540 and when I applied power, I could have sent smoke signals across town. And Maris fixed it for free. Can't beat the Gecko drives for their support. Not many companies would have fixed something for free that was caused by my own extreme stupidity.