SRVO-045 Error - UPDATE SOLVED!!

[Robotic Metallizing]

Hi guys,

I posted a while back about some issue with memory and freeing up space on the ram disks, I have since found my solution, or so I think, which i have not been able to test as of yet due to a steady flow production without any downtime for development. Long story short, I'll post my results for those who may still be working with these dinosaurs like me.  New issue to talk about now.

The other FANUC S-10 R-J controller robot we have is throwing a SRVO-045 error on Group 1 Axis 6. I read in other posts related to...I think it was a SRVO-146 error, that the cables should be checked with a megger and verified to not have an insulation leak. In addition to this the motor could be an issue as well as the motor leads. The cables being discussed were the cables running from the controller to the rear base of the robot?

On the first robot with the memory issue a similar instance occurred relating to the over voltage on the amplifier, the root cause was found to be an issue with the small boards on the amplifier circuit, if I'm not mistaken the faulty components were capacitors.

I'm not super familiar with these robots, more of an ABB guy but this task has been passed off to me. Inside of the controller on the left side are three vertical board assemblies, and on those vertical boards are the "computer-chips" for lack of a better name right now that I am referring to. I've been told these have been swapped and the problem still persists. I can try swapping boards to different locations to see if this makes a difference and moves the error to a different axis.

Let me know your thoughts and thanks ahead of time for the help you guys offer!

-Zack

[raycor]

Hi, SRVO 045 in a RJ controller is:
SRVO-045 ER_SVAL1 HCAL alarm(Group:%d Axis:%d)
Cause:
The current in the main power circuit of the servo amplifier exceeded specification.
Remedy:
Disconnect the motor power wires from the servo amplifier and turn on power. If an HCAL occurs, replace the transistor module or servo amplifier. Measure the resistance between GND and U, V, W individually on the cable terminals. If shorted, determine if the cable or motor is bad. Check the resistance between U-V, V-W, and W-U using a measuring instrument sensitive enough to detect small resistances at the cable terminations. If the resistances are not the same replace the servo amplifier. If the resistances are different, determine if the cable or motor is bad. If the problem persists, replace the SIF module on the axis control for the defective axis.

Practically, you need to see why the 6th axis is going to collision, then you need to check if the motor is damaged, check the grease of axis 6 that dosn't have any particles of metal if it has, your 6th gear is damaged, check the wire that goes with the robot from the base of the robot to the 6th motor, check the RM1 cable, in this order you can solve the problem, if this this doesn't solve it, maybe you need to go slower with speed, you can see how the robot works with a speed of 90% or if you need go till 60% decreasing in 5%, with this you can check the motor, if you take out the 6th motor from the robot, check also that can turn back and forward without limitation.

[Robotic Metallizing]

 

Friday evening while the process portion of the shop was closed for the day I managed to pull the amplifier from the controller and swap out the drive control modules with two of the three spares I have laying around, the error persisted. Just to be sure I then swapped the previously installed drive control modules with those from the servo amplifier for axes 2 & 5, the error persisted on axis 6, but in doing this test I ruled out that the drive control modules were @ fault by taking ones I knew to be working from another amplifier and verifying that my spares were good by them functioning properly in the 2 & 5 amplifier. Luckily enough we have another one of these robots so I was able to pull the 3 & 6 axis amplifier from the robot and install it in this robot. No more error and after 70 some odd cycles for a production run I have come to the conclusion that the amplifier is at fault this time. I have a refurbished one on order, it should be in tomorrow from my supplier and I will post an update.

I will check these cables as well because I can see the cabling is in some pretty rough shape and is sure to be an issue somewhere in the near future. Thanks for the help raycor!

[Robotic Metallizing]

Alright! I was able to successfully get the robot working. Here is what I did in case someone runs into similar issues and is looking for help...

Like I had said in the initial post I was getting a SRVO-045 fault Group: 1 Axis:6 and sometimes depending upon the movement it would fault to axis 3 instead, in either case both issues pertain to the same servo amplifier and hardware.

I was initially leaning towards the issue being a drive control module, located in the two middle slots on the servo amplifier and given that the fault would occur on two different axes at different time maybe both were intermittently failing. I removed the amplifier and swapped the drive control modules and reinstalled the amplifier only to find that the problem persisted.

I then thought "okay, maybe my spares are bad" (after all I was not the last one to work with these robots and capacitors (on the old style board) can dry out being on the shelf or in their past life in the robot.)

I removed the amplifier again and pulled the axis 2/5 amplifier as well, swapped the drive control modules, reinstalled the amplifier only to find that the problem still persisted.

Okay so drive control modules are ruled out.

Just so you guys know when the robot is faulting out...in my application the traverse speed of the robot is extremely critical to provide and even distribution thickness of material, in this case only maybe 2-5 mm/s sometimes a little faster and sometimes it drops down to 1 mm/s. I can't slow this down, I'm at the bottom end of the speed as it is.

Luckily I have a second identical robot... I swapped the entire amplifier this time from that robot into this one and the problem was solved. I ordered an amplifier as I had stated and received it the next day. Installed the amp and the problem almost immediately occurred after the robot booted! I was also receiving I think it was a SRVO-023 error or the code that pertains to too low of a voltage on the amplifier.

Not a good start to the day.

Going back through everything and second guessing myself I was positive this was the issue and the amplifier I received was faulty. I had another one shipped in the next day, replaced it a second time and everything is running strong. I am thinking there is a loose board or connection on the 1/4 amplifier as the slightest bump to the console with cause it to fault on axis 4. Something I will check in the next few days here.

Thank you for the help raycor and best of luck to everyone else on the forum!

-Zack

[Robotic Metallizing]

Just an update, the original amplifier I received was indeed faulty and causing the issues I was having. The drive control modules, cables, harness, were all fine. The amplifier is installed with fanuc OEM 3rd generation new style drive control modules and the robot is running strong for its twentieth birthday coming up in a year. Might just be time to crack open a bottle of champagne! Thanks for the help along the way!