Is my 320 fried?

[DAB_Design]

I pulled the table off my machine today to clean some gunk off. When I got the Y slide back on, I mounted the motor and started to run a 'warm-up' program on Y only. Well nothing happened. Fault light was not on. Checked all the cables, and all were connected good.

I got out the multimeter and checked a few things. No power at the motor leads. Powered the drives down and disconnected the motor leads from my case. Powered back up and checked the plug at the case. Nothing. Opened up the case and checked at the fuse. Fuse is ok. Power at +18 to 80 checked 67.7. Checked at Arm - and Arm +. Nothing. Shouldn't there be something there?

I didn't see/smell anything like burning money...er...I mean electronics. Anyone have any ideas? Please don't say it's a pretty paper weight now. Can't really afford to get another one. Kind of a bad time a year, ya know?

[sol]

First the easy checks...
Do the other Axes work?
Is the 5v line to Gecko Y hot?

[ViperTX]

Check your connections. When the Gecko is turned on....direction, step....the arm + - will have voltage applied.

[DAB_Design]

OK lets see....

Sol, yes, X and Z were unaffected. I actually had my Y axis running off the Z gecko last night. My Z axis isn't converted yet, so it's open.
I'm assuming the 5v was hot. I'm pulling it from the PC driving the geckos.

Everything on the gecko seems to work, except getting power to the motor. The fault light turns on when power is first applied. Clear the faults and X axis would energize (Z axis wasn't hooked up). Y axis motor can be spun by hand. But when spun just a little, it causes the fault light(s) to come on on the gecko (it faults when the encoder is 128 counts off, right?). So the encoder is getting power. Just not arm -/+.

Ok, that was the easy stuff. Now what about the hard stuff?

[sendkeys]

if everything works with the z gecko switched to the y wires. sounds like the old y gecko is dead . Might pull it apart see if you can see anything burnt up. any copper on the board melted ect. Some times that is easy to fix yourself. if not m sure gecko will not have a problem testing it for you. Only thing will be the wait but with the sale prices now might be a good idea to have a backup gecko around anyway. might also try the basic smell test does it have a nice burnt smell? :P

[ViperTX]

That is the only problem with these encapsulated units...you can't fix them very easily....I'll opt for Geckos as I design my own servo driver.

[DAB_Design]

Nope, no magic smoke smell. I'll pull it apart tomorrow.

[sol]

I'm not sure that I understand what has been done.

When running axis Y with Gecko Z was Gecko Z completely replacing Gecko Y or were just the motor and encoder cables switched from GeckoY to Gecko Z?

What is the setting of the Current trim pot on Gecko Y?

Are you absolutely positively sure that the encoder or power cables have not been switched Pos to Neg. Having them reversed will prompt an immediate fault when the Gecko attempts to turn the motor.

Notice that in the Gecko directions the Red is Neg and Black is Pos
Wouldn't it be nice if that were the problem?

Good luck!

[Mariss Freimanis]

DAB Design,

Did you put an Ohmmeter across the ARM+ and ARM- terminals of the drive (power off of course)? You should see the motor armature resistance.

A voltmeter will give you very little information. The voltage across the motor is a 25kHz squarewave having an amplitude equal to your supply voltage.

Mariss

[DAB_Design]

Mariss, sorry for my ignorance, but my electrical ability is somewhat limited. I tried what you said and my ignorance shows below.

Using the ohm meter (with power off to the drives), I checked X Y and Z drives. No motor is hooked to the Z axis. With the Ohm meter set at 200K (meter has 5 settings starting at 200 through 2000k and 200k was the only setting that seemed to give, what I believe as, a believe answer) X axis would flash a number (double digit), then almost instantly go to zero. The initial reading wouldn't stay long enough for me to see what it said.

Y axis would do the same. Flashes a double digit number, then go to zero.

Z axis however, with no motor attached would read 92.5 +/- a couple .1's. Not sure if that's expected or not.

[ViperTX]

Originally Posted by DAB_Design Mariss, sorry for my ignorance, but my electrical ability is somewhat limited. I tried what you said and my ignorance shows below. Using the ohm meter (with power off to the drives), I checked X Y and Z drives. No motor is hooked to the Z axis. With the Ohm meter set at 200K (meter has 5 settings starting at 200 through 2000k and 200k was the only setting that seemed to give, what I believe as, a believe answer) X axis would flash a number (double digit), then almost instantly go to zero. The initial reading wouldn't stay long enough for me to see what it said. Y axis would do the same. Flashes a double digit number, then go to zero. Z axis however, with no motor attached would read 92.5 +/- a couple .1's. Not sure if that's expected or not.

I suspect that your armature resistance is down in the single digits.....like 1.7 ohms. To measure the armature resistance, disconnect the motor from the Gecko and measure across the armature pins of the motor.
On the Z-axis I suspect that you are reading across the Gecko's FET bridge....hopefully it has some components to keep you from blowing the FETs.

[ViperTX]

DAB_Design,

If you've tried another working motor with that Gecko and you don't have the Gecko current limited to some low value, and it's properly connected then the Gecko is dead.

Perhaps the warranty is still valid....I'd send them a message....which they probably won't ever answer....at least they've never answered my emails.