Screwy Behavior

[nitewatchman]

I added the 24VDC circuits for the Hot Bed last night and it works very well. Thank you very much.

Another problem has surfaced. When I try to HOME the axis, they take off like a bat out of hell and run full speed towards the bed. This is different from the problem I had before where they would go down a small amount and stop due to zero being set to high.

I did have the Rambo out and all the cables loose BUT I believe they went back where they belong and the end stops tests are successful for both the closed and open switch. Even in Repetier the travel is inverted although it will only travel a short distance. I have tried setting z zero on the bed and high on the towers, makes no difference.

Any ideas.

[BenTheRighteous]

Did you install the stepper connectors into the rambo board backwards?

[nitewatchman]

I thought of that but I don't think that you can.

Item added to the check list!


Thanks!

[BenTheRighteous]

Maybe you got the Wantai motors, but I can definitely connect my Kysans backwards!

[nitewatchman]

It's been running for 6-8 months before this.

[nitewatchman]

Any guidance?

[BenTheRighteous]

Are you absolutely, 100% positive you didn't connect the steppers backwards?

I just now opened up my machine and reversed my X tower stepper connector just to see what would happen. Yes, it fit. And when I selected Home Towers, Y and Z went up no problem. X went crashing into the floor (or would've if I hadn't hit the power switch).

So, until you say that you FOR SURE have your steppers connected right, then my advice remains to reconnect them right-way-around this time.

[nitewatchman]

Sorry Ben,

Tried again and my plugs are definely polarized and only fit one way. While I agree that this could do it I just can't get them to fit.

This has to be something as simple as the plug turned over. But I can't find it.

[BenTheRighteous]

Yeah I agree - it's got to be crossed wires. (At least I'm assuming at no point did you upload firmware - I don't see why you would if you were doing the 24v mod - right?)

I guess at this point I'd start testing input voltages into the RAMBo. Make sure that you're getting +12v where you expect and not -12v by mistake.

[nitewatchman]

Checked, rechecked and rechecked again. Could not find a wiring or voltage problem. In shear frustration, I went back to the manual and started doing the assembly again. Cleared the EEPROM, uploaded the firmware, problem solved!

Go figure!

[BenTheRighteous]

Awesome! Glad to hear you got it worked out.

[teoman]

I was going to suggest undo the thing you last did. I.e remove 24b supply, it could be creating noise that is affecting limit switches.

Anyhow. Glad you got it sorted.