[grecout]

new to these stepper motors and running nema 34 1200oz. 7w. on a knee mill
and I have no torq. I can hold the 2" gear with my hand and try to run motor
with very little effort stall motor can someone help?

[harryn]

Hi, maybe a little more info will allow users to at least make a guess. I know these are kind of basic, but let's start with the easy questions first.

- Motor model information
- number of wires
- Driver information
- Power supply voltage
- wiring diagram

BTW - has the motor ever been apart ? For reasons that are unclear to me, this seems to ruin them.

[grecout]

Harryn thanks for responce
here is the information on the motors
REX 1200 oz. in. Hybrid stepper motors with 4 wires (bipolar)
7amp. stepper motion control using geco drivers with 100k resisters
Rapid 55vdc/700W tolroid coil power supply 120vac
purchased sys.new from logitrol systems.

[harryn]

Hi - ok, that is a good start. 1200 oz in - pretty nice. Is there an "amps" and mH rating on the motor ?

Is this brand new hook up with problems or a problem with a previously operating setup ?

I don't know that much about Gecko drivers, but 100K ohms seems like a lot to have in series with a driver. I don't have any idea, but a place to double check.

Switch to full steps - no microstepping for some testing.

When the motor is in "idle", the gecko's usually will reduce the current to prevent overheating. Is this possibly what you are seeing ?

I am assuming you are running mach and the output signals look ok ?

Do you have any spares to swap around or are we working with just this one set ?

[Crevice Reamer]

Hi grecout. Welcome to the Zone!

WHICH Gecko drives are you running?

CR.

[grecout]

Harryn
there is no amps or MH rating on the motor,
brand new hookup,
switch to full steps ? I don't understand,
when motor is in idle and quill is down and motor is powered up I can push up on the quill and move the quill up all the way with very little effort,
yes running mach3 and ? where do I check outputs,
yes I have 2 other motors that are hooked up to X,Y, and I will switch one out with Z and let you know

[grecout]

Hi CR I'm not sure what gecko drives I have how can I tell

[Crevice Reamer]

It should have a G number right on the drive. What color are they?

CR.

[grecout]

CR
the greco drivers are red or bergudi in color and it looks like the # G203v

[Crevice Reamer]

Ok. Is anything connected to pin #7?

Are any lights lit on the G203V? If so, what color are they?

100K resistor on G203V will limit current to 4.75A. 7A current limit setting on 203V is NO resistor. Try it like that if you are SURE that you have a 7A motor.

CR.

[grecout]

CR what pins are you talking about and if they are on the gecko drive then counting from left to right #7 looks like one red wire and it goes to engage
motor switch

[Crevice Reamer]

OK, try to run it and see if any lights are lit on the G203V and what colors they are.

CR.

[grecout]

CR no lights flashing just power light no Z axis geckodrive stays lit and it is green

[Crevice Reamer]

Are you saying that all the other Geckos have green lights, but the Z Gecko has NO light?

CR.

[Crevice Reamer]

Okay, I think you typed no instead of on. So Green light is ON for Z Gecko.

I'm going to bed. If you have a green light on Z G203V, shut off power, unscrew and remove current resistor. Now try it and see if you have torque.

CR.

[grecout]

No I'm sorry all three geckodrivers have green lights and all stay on when powered up

[Crevice Reamer]

Right! Now disconnect and remove the resistor from the Z Gecko (2 screws on right side of terminal) and try it then. If it now works, you will need to replace that resistor with a 282K resistor.

CR.

[grecout]

ok I think I did what you said on Z gecko drive the 2 screws on the right side have one blue and one white wire that leads to a wire connect that holds the 100k resister, at that location I removed the 100k and left it open, powered up machine and was still able to hold the quill in one spot when trying to feed so I got no change. keep in mind that as far as I know it caused an open circut by removing that resister is this true ?.

[Crevice Reamer]

NO resistor on a G203V sets it to ouput 7A. That rules out the resistor, and you can reconnect those wires.

The drive is apparently good. I now suspect that somehow this motor is not connected right. Please check all motor connections at the drive and at the motor.

Or it COULD be the motor itself.

CR.