Problem- Series I Boss 5, All axis dead

[timprebleco]

Guy's
A freind just gave me a Series I Boss 5 Machine. I apears to be in really good shape mechanicaly. I got it home and powered it up. None of the axis will move. There is no power going to them to either "brake" or move. The controller will program and the aixs read out count as if it is moving but it is not. I have checked the regulated and unregulated voltages and they are good. Spindle motor powers up and the brake and speed control work. The ERS board comunicates with my PC.
The only thing that seems to be wrong is the X,Y & Z are all dead. Any sugestions. I have a Boss 6 manual and have checked about everything, There just does not seem to be power to the steppers. What am I missing?

[machintek]

First, did you press in the limit over-ride button? Probably OK since spindle starts.
Check power at fuses 12, 13, and 14. this is power to the drives-each axis. Should be about 9 to 10 VDC is drives are on. Check 54VDC power supply.

George

[timprebleco]

George,
I just sent a reply saying that all my voltages looked good. I just realized that the ACC Board is missing.
Took the ACC board out of my Boss 6 (that is having Y axis problems as well) put it in and now I have the Y axis moving in both directions and the Z axis moving down only and the X axis hums and tries to move like it is stepping but will not keep turning. I have switched the SMD Boards around and the Z axix goes up and down both now. But nothing else changed. I have flipped the Acc board and no further change. Will replacing the transistors fix this?

I am running off of a phase converter and although I have ballanced the 220 legs, I still have a voltage of 235-243 between any two legs, which I belive is running my 54V DC a little high, about 60V. According to the book the Max sould be 59V, Is this enough to cause me problems?

[machintek]

There are a LOT of possibilities. A transistor could be weak. You may have one diode on the bridge rectifier for that axis opem. A diode could be shorted on the board to the bottom right of the SMD boards or a screw or chip could have fallen between the diodes or the wires on the terminal strip going to the motors.
ETC.

George

[timprebleco]

George,
Thank you for the quick responses. I am going to try to get and keep both of these machines running untill I can afford retrofits for them.
I have a freind that has a scrap machine and has offered to sell me the whole set of resistors. Between those and the two machines that I have I should be able to have enough good parts to have something going by tomorrow or the next day. I will continue to post updates.
I read an older posting that talked about adding Schottky Diodes as a possible way to keep this from hapening again. Do you have any experience with those and if so would you be able to make a recomendation as to the size required? I will start a new thread and ask the Schottky Diodes question again.

[timprebleco]

George,
Thanks for the help!
I have both machines up and running on all three axis each. I had to replace three sets of transistors between the two machies. I had a freind sell me three complete sets still mounted in the brackets. That made it a lot easier to change them out. Now I have to figure out how to find out which are the bad ones.
The Z axis motor on the Boss 5 sounds bad on start up and shut down when joging. I removed the belt and just ran it. It is sounds fine when running full speed but it growls when stepping and stops and hums while under load in rapid. Is it bad or do I possibly have another problem?

[machintek]

A growl is "normal" since the machines step hence stepping motors. The BOSS 5 steps in .001 steps. The BOSS 6 will step in .0005 steps.
AT rapid they will whine which is the growl of higher frequency.
But it is hard to define normal. Check for proper oiling, proper current, etc.

George

[timprebleco]

George,
Boss 5
I replaced the z axis motor this morning and the growling stopped, but it would still stall out in rapid. All axis were moving.
I hooked up the computer to download programs and powered it up and now nothing moves. I found a blown fuse on the board above the SMD boards where the transistors are located. Now the only thing working seems to be the spindle motor, the brake and the speed change.
Boss 6
I changed out the transistor bank on the Y and the X axis yesterday. It was moving again. I was getting ready to set up a job on it after I changed out the transistors and now the Y axis is not moving again, just like there is another transistor blown.
What the heck is going on? Both machines were ready to run in the morning and both are down again tonight whith out even been set up or ran. This is like out of the Twlight Zone or something.

[A.A]

Hello timprebleco,
Hope you will be fine. Timprebleco, i am facing exactly the same problem as yours. I powered ON my series 1 after more than 2 years and found that neither the Z axis nor the Yaxis was working fine, these motors are producing Hummmms and there shafts are not turning around. Only the x- axis was working fine.
I tried my best checking any disconnected wire but nothing came out. In the end i inter changed my X and Y SMD boards and as a result i lost my X-axis toooooooooooooooooooo....

I have checked all the transistors on the SMD and ACC boards and only one small transistor on the Y- axis SMD board came out to be faulty. But i have not checked any of the transistors mounted on heat sinks at the back of machine.

After reading your posts i realized that you can be the only person to guide me out of this problem.