I tried to follow your recommendations, but am getting no 115v applied to the contactor. Do I need to route that through COR?
I tried to follow your recommendations, but am getting no 115v applied to the contactor. Do I need to route that through COR?
temporarily bypassing ACC in order to get some other progress made, but when I turn on the machine, the Z Axis instantly turns on and runs to both limits repeatedly. I unplugged the Z motor from the servo amp and checked all the inputs. They are consistent across TB6 for all axes:
Limit Ground->Positive is ~12v
Limit Ground->Negative is ~12v
(Obviously not at limits)
Tach->Tach Return is 0v
DAC->DAC Return is 0v
Only the Z axis is running, EMC reports all axes at limits. Any ideas what is going on??
*Edit*
The 7i37 is getting 2.3V, I assume that since it is either a 3.3v or 5v system, that's why I'm reporting consistent limit conditions.
Point of Interest:
When you do wire your E-Stop, if you can maintain power to the encoders you will not need to re-home the machine when coming out of E-Stop. ( Assumes the machine was homed since initial power up.)
With regards to the 115 not getting to the ACC relay. Do you still have 115VAC connected to the control relay board? If not, it should be connected to TB2-1 and 2 (hot) and TB2-23 and 25 (return). Just to be sure, TB2 is the terminal strip on the right side of the control relay board and TB3 is on the left. Check that the fuse at the top of the board is also intact.
With regards to the limits. The X and Y sensors are essentially transistors. I'll look at the spec sheets and app notes again. For them to work properly a resistor may need to go between the sensor output and ground and then pick up the digital output from the sensor output/resistor connection. However, if I'm not mistaken, the Z is using mechanical switches. You should be getting a solid voltage level for the limit switches there. Do you observe any changes to the limit inputs when you force a limit condition? Does the 12V you mentioned go to 0V or does it stay at 12V?
Moving back and forth between the limits sounds like your servo loop is running away. Do you still have the tach connected to the servo amps? If not, reconnect them, the amps need the tach to close the analog velocity loop. Remember, the DAC input is a velocity command to the amplifiers. The pots are used to tune the velocity loop inside of the amps. If you take away the tach, the loop has no feedback.
If you have a scope, connect it to the DAC input on the amps. If you only have a meter, try it. Does the voltage change when the motor changes direction? What voltage is going into the DAC input? Do you have the command voltage from the 7i37 configured as a bi-polar output? The amps expect to see voltages that go between +10V and -10V.
Still working on this, I've gotten the Z axis working, but when I try and use either the X or Y axes, both move at Rapid Traverse until either a "Following Error" has been reached, or a "Soft Limit." They work perfectly if a 9v battery is applied to the DAC.
A few stupid maneuvers later, all table axes run. When I try and fire up the VFD to run the spindle, however, it causes all the axes to drive in the negative direction, in addition to running the spindle.
Does the ACC contactor act in some way like a diode, and prevent electrical backflow? I think the VFD may be pulling too much current down.
Thanks
This evening I made my first CNC'd parts on my retrofitted Hurco, a big thanks to rballister, bloke, gthlm, jackal66, and Al_The_Man for their tireless help!
It is a great feeling - isn't it?
Nice work!
sam
Congrats on getting it working. What was the resolution to the last few issues? I was on vacation and was out of town for a while. I was thinking that maybe the motors were wired backwards.
BTW, thanks for the parts. I did get them and they'll be helpful in getting some of the details working.
If you can, post some pictures. I'd be interested in seeing how things turned out.
Mostly problems with wiring, I highly recommend puling any and all wires not being used out of the machine to make things easier to find/wire up nicely. I still haven't gotten a good hard E-Stop which I'm a little worried about, but it's behaving very well now.
Basically I needed to ensure that the motors and encoders were wired in the same direction to prevent runaway motors trying to get to position and continuing to go further and further from where they belonged.
rballister, if you need any more parts don't hesitate to ask, I will probably make a list of all that I have to help people who are looking.