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So…I got my ATR going yesterday and spent an hour or so running it through its paces. Very impressed. When I got done, I put it on the charger until the green light came on. So far, so good.
When I started up the robot, the red error LED was flashing and I only had one channel operational. I checked battery voltage and it is 27.4 V in a 24 volt system. I know the controller will flash the error LED when voltage is too high, DELink shows the controller has a high voltage setting of 31 volts.
What am I doing wrong?
OK, to narrow your problem down can you try disconnecting the RC signal and motor that aren’t working from the sabertooth and see if you still get an error light?
Also, you can try swapping sides between the RC signals and motors. We need to determine if the issue is with the motor controller or the motors.
OK. I disconnected the RC receiver and the affected motors (Same side). No change. The red error LED is still flashing. Checked voltage at terminals strip for each side and the affected side gets 0 volts and the good side gets 21.4. Either the controller has gone belly up or the high battery voltage is not allowing it to operate normally.
I am looking into ways to drain the battery down to a more reasonable voltage and see if that solves the issue. All was running perfectly until I charged then battery packs.I was led to believe that the DEScribe software would allow me to change the high voltage threshold to prevent this from happening, but apparently that is not the case. I have the high voltage set at 31 volts
This is getting ridiculous…..
We will check with dimension engineering, but the 2 x 12 RC is rated for only 14V nominal and with the LiFePO4 batteries, the peak voltage may be causing the trouble, despite the settings DEScribe is allowing you to put in. There also may be some damage caused by the capacitors that were causing the ferrite beads to overheat. We can send you a replacement 2 x 12RC, but you may still have some issues with a peaked battery. I think your best bet is the new 2×32, which is rated at a higher voltage tolerance. Its a little more money and we can refund the cost of the 2 x 12RC towards the cost when we get it back. Sorry its proving so difficult/frustrating, unfortunately robot building is not simple, there are always some things that come up. When we assemble the robot kits ourselves we typically go through similar issues. The advantage being we have a lot of experience troubleshooting and lessons learned and have the advantage of being able to swap suspect parts out easily. Give us a call if you want to get a replacement or upgraded Sabertooth.
I appreciate your help. The controller I have installed is the 2×25 and was upgraded on the advice of the sales guy I talked to when I placed the order. The damage from the capacitors may be the issue, but the machine ran perfectly after removing them and only stopped working correctly after I charged it.
I understand these things aren’t an exact quantity and I’m sure we’ll figure it out. My biggest concern is that this robot is going to be put into service and needs to be able to be charged without the drama I am experiencing now.
Could you look into the 2×32 controller and see if its voltage threshold is higher than the 2×25? Thank you for the help.
the 2×32 is the newer controller. One of the reasons the new controller was build was to deal with the higher voltages of lithium batteries. The 2×25 V2 is actually been updated to have the same rating. They are both rated 6-30V nominal, 33.6V absolute maximum. The 2×25 you have will be a V2, we don’t have old stock. So its up to you we can send a replacement 2×25 or a 2×32, they are the same price. The 2×32 has slightly larger footprint and mounting holes.
It certainly sounds like the motor controller is not working right. There are a ton of other things that it could be too. Motor wiring, grounding loops, bad power, loose terminals, power issues, etc. We will be happy to send you a new one, but it may not solve the issue. Make sure you have fully isolated it to the motor controller. Swap right and left motors in the M1 and M2 and make sure it is still the same side of the motor controller. if the issues follows the motors, then its you motors. Only hook one motor per side to start.
Once you get it working right, it will keep working. Most issues are only during startup and hookup. The LiFePO4 should never get over 30V.
Thanks for the direction. I tried the non-operating motors on the M1 terminal and they both ran fine, so the motors are good.
I called Dimension Engineering and spoke to Charlotte. She came to the same conclusion as you that the controller is toast. She sent am RMA for me to send back the controller and they will diagnose the problem and either repair or replace the controller.
I’ll let you know what the verdict is.
And a bit of chiding is owed you…the capacitor thing is really disturbing since the instructions say to install them straight away. I would change that to keep the same thing from happening again. Just sayin’…. :)
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