Need Help!- z axis full power without motion

[milawatt]

Well, I guess I broke my mill today. It Is an M60 on a millport. I ran the z axis into the top of the block I was going to machine. Before I could trip the e stop it shut itself off. I jogged the z axis back up and got a z axis + limit switch error. I took off the cover on the spindle and jogged it down a little and the z axis limit reset. Now the problem is this, when I power up, every thing looks good and normal until I home the machine, then get the Z axis full power no motion.?? there is no power to any of the servos. What do you think??? thanks

[MarcL]

It could be any number of things: blown servo drive; damaged servo motor; failure to release holding brake in servo motor; physically jammed head or screw; etc..

Power up, and without bothering to try to home, switch to Slow Continuous jog mode.

Can you jog X and Y in both directions?

Can you jog Z down?

If you are sure Z is clear of the switch and the end of travel, can you jog Z up?

Are all of the Green LEDs on your servo drive unit lit?

Do you know whether your Z servo motor has an integral holding brake? If you are not sure, see if there are any wires connected to the two brake screw terminals low on the left edge of the drive.

If you can turn the Z motor or screw with the power off (e.g. with E-stop pressed in) see if you can jog Z successfully after moving it a little by hand. If you can, but it stalls again in the same spot, then you probably have a burnt spot on the commutator of your servo motor.

Let us know what you find out.

[milawatt]

MarcL, thanks for your reply, I tried to jog without homing, I got the error message X full power no motion, same message for Y and Z. I could not jog Z. I manually turned the z belt down so it is in the middle of its travel. As to the drive board. there is a vertical row 6 lights and a row of 3 to the right. The top 3 are green, the bottom 3 which say X,Y and Z are red. the right side 3 are this, top says USV is not on, the middle says OV is green, the bottom says UV is not on. On the bottom of the drive board are some terminals, red and black wires X+ ,X- and so on the right side has a +VM label It looks like this is drive board power, it has no voltage reading, as does the X,Y and Z terminal. The machine was working great until I crashed It. Am I missing some sort of main reset . I did check all of the fuses I could find, all good. any thoughts?

thanks again,

[the-depot]

With the Estop released do you have power to the driver board? If not check the transformer for the servo drives AC volts. there should be a fuse for this transformer. Input and output. Be careful with the Hi Voltage DC it is very dangerous. This voltage goes through the Estop Contactor . You need to see if it is on both sides of the contactor. If not keep working your way back till you get a reading. The volage on the back side of the Rectifier is AC you will have to change the meter to read this. Don't feel bad I have forgotten to set the part Z and you cannot get to the Estop fast enough. I can tell you, I always remember to turn the feed rate down on the first part now. The driver is pretty tough It has alot of built in safety factors. hopefully it is something simple.

[milawatt]

To the-depot,
I thank you very much for the tips, I followed your steps. I had power everywhere, fuses good. I looked carefully at the factory elec drawings, which are faded badly. I followed the blue power wire for the axis drive. I had power on both sides of the E STOP contactor, Also I held It in with a wood dowel, the red lights on the drive board went off. I pushed the home button and to my great thrill , It homed itself. I could then jog all the axis fine. As soon as I pulled out the dowel, the red lights came back on. I am looking at the drawing, I cant see where the conntactor gets its on power from. To my relief I did not blow a motor. Ill keep tring to see why the E STOP has no pull in power. Your suggestion on turning the feed rate down was well taken, I have been using an EZTRAX for some years, as you can see I am new to 3 axis programming. If you have any tips on the ESTOP not pulling in, Id like to know. Thank again

[MarcL]

That is significant progress. Evidently drive and motors are okay, VM motor power is okay, but your E-stop contactor is not closing when you release the E-stop button.

Power for the E-stop contactor coil is 24VAC. It comes from an additional set of secondary taps on the big transformer (usually with Red and Brown wires). From the transformer the 24VAC power will go through a noise filter, then to the 2-position orange Phoenix plug on the short end of your RTK2 PLC unit (adjacent to a 4-position plug with 110VAC).

The Brown side of the circuit will come out the bottom-most terminal of H9 (a 12-position orange Phoenix plug on the lower right side of the top board of the RTK2 unit) and should go directly to one side of the contactor coil.

The Red side of the circuit is fused on the RTK2 top board (F2), then goes out the second-from-bottom terminal of H9; goes through the E-stop button in the console; goes through the RLY1 and RLY2 terminals on the servo drive; then to the other side of the contactor coil.

So, if your contactor is not closing, you need to find out where you are losing the 24VAC. Check voltage across the noise filter and/or on the 2-position plug going into the RTK2; check voltage across the bottom two terminals of H9, coming out of the RTK2; check from the bottom terminal of H9 to the RLY2 terminal of the servo drive; then from the bottom terminal of H9 to the RLY1 terminal of the servo drive.

If you find that you are losing it across the RLY1/RLY2 terminals of the servo drive (confirmed if you measure approx. 24VAC from RLY1 to RLY2, meaning the relay must be open) then check the Green "EStop" LED on the drive (below and a little in-board of the other LEDs you noted). It should be on. If it is not, check the security of the nearby 4-position brown Waldom plug.

Again, let us know what you find out.

[the-depot]

I am glad the motors and drives are ok. the Estop goes through the plc on the driver board. It could be something on the board that is keeping the estop loop open in the PLC take a look at the Estop contactor coil is it 115V or 24V see if you have the proper voltage accross the coil when the Estop is out. if you do then check the coil with an ohm meter to see if you get a reading( do this only with the power off) also check the button itself to see of it is allowing the current to flow. the Estop should have two sets of contacts, one goes to the an input on the PLC to tell the controller the position of the Button and a hardwired loop for the Estop contactor. try to find where you are loosing the flow of current to the Contactor. Let me know

[milawatt]

MarcL, thanks for the possible problems, the small connector from the noise filter Is 26.5 V,from bottom of H9 and rely2 is 26.5 V, from H9 bottom to rely2 is 26.5 V. the bottom 2 wires measure 26.5 V. the measure between rly1 and rly 2 is 0 V. the green estop led is on green. Im begining to think one of the boards is damaged some how??? what do you think??

thanks again

[MarcL]

No evidence of a damaged or failed board. Right now it sounds like power is not getting through your E-stop contactor, either because the contactor is not closing or because the contact points inside are burnt or damaged.

When you press and release emergency stop on the console, do you see and/or hear the contactor clicking in and out?

The UV and USV lights on the servo drive indicate the presence of the motor power supply (ca. 120 VDC on terminals 9 and 10, "Gnd" and VM). This power comes through the E-stop contactor, so the UV and USV lights should go out when you press E-stop, and should come back on when you release E-stop and allow the contactor to close.

If the contactor clicks in when you release E-stop, but the UV and USV lights stay out, but you can make them come on by pressing on the contactor with a dowel, then you probably have burnt contacts inside.

If the contactor does not click in when you release E-stop, then you need to continue looking at the 24VAC loop.

[Motorcoach1]

Originally Posted by MarcL No evidence of a damaged or failed board. Right now it sounds like power is not getting through your E-stop contactor, either because the contactor is not closing or because the contact points inside are burnt or damaged. When you press and release emergency stop on the console, do you see and/or hear the contactor clicking in and out? The UV and USV lights on the servo drive indicate the presence of the motor power supply (ca. 120 VDC on terminals 9 and 10, "Gnd" and VM). This power comes through the E-stop contactor, so the UV and USV lights should go out when you press E-stop, and should come back on when you release E-stop and allow the contactor to close. If the contactor clicks in when you release E-stop, but the UV and USV lights stay out, but you can make them come on by pressing on the contactor with a dowel, then you probably have burnt contacts inside. If the contactor does not click in when you release E-stop, then you need to continue looking at the 24VAC loop.

this might sound funny but on some of the Semians - Irion controlers we have in our machines I have found that the crimp on the wire terminal was bad and recrimping to get a good connect worked , as far as the 24 volts in the contactor I have found the coil can't take much load at dead stops and get fried for some reason- so I always have a replacement till I can determine if the unit is bad , to keep me up and running. I feel the back BEMF spike takes them out in the hard shut down. just a thought. PS is the contactor in 2 parts the relay and the coil the coil part has a built in current limiter and that can be replaced the contactor is a seprate part and that can be replaced too if you have a gren lite that shows the cuirct is good and the coil has no voltage to pull contactor , I would check the coil and there is an adjustment to incress the current , is it a 2.6 or lower contactor ?

[MILLMANM]

Today I tried to fire up the mill and got the same alarm. e stop not working
Last week i started it up and it homed good, but i had a little problem getting the spindle to move but it did with a little help and I left it run for a while ,the machine has not been running in 256 days,

found what I think is the red estop wire had fell out of the contactor and went to ground so I replaced it to A2 but did not work ,need to do more checking of voltages

it is 105 in the garage and now getting a error when it tries to boot
07-29-2008 2:29:34 102 Error initializing CPU...cannot continue.
07-29-2008 2:30:00 Exiting CNC10 due to a known error (63)
Dual port base address = d0000
Timeout: 64180 not responding
Error occurred sending line 54
102 Error initializing CPU...cannot continue.
Return code 63

any ideas
will check volts in am

hope we can get this problem fixed
dose anybody have the username \password for ajax tech please pm me it has been awhile sence I had to use it
Thanks

[cncsnw]

Timeout: 64180 not responding Error occurred sending line 54

This is completely unrelated to the previous issues surrounding the E-stop contactor. This message indicates that the control software, running on the PC, did not get any response from the CPU7 board across the PC's ISA bus (expansion slot).

Try it again when the temperature is more reasonable. If you get the same message, open up the PC case; mark and unplug the five optical fibers; remove and reinsert the CPU7 board; return the optical fibers; and try powering up again.

The E-stop contactor will not close if the PC software has not started up successfully. That is because the PC software needs to start up the CPU7 board, and the CPU7 board needs to start talking to the servo drive, before the servo drive will close its RLY1/RLY2 terminals to complete the E-stop coil circuit.