Magnet not detected

Troubleshooting
1

I’ve just upgraded my control board because of the z-axis not working problem.
After upgrading the firmware, maslow.yaml and index.html.gz files I now seem to have a belt problem.

  • If I try to move the z-axis up or down the messages “Maslow is not ready to move.” and “Could not perform Jog. Belt lengths are unknown.” are displayed.
  • Pressing the “extend all” button causes the top right belt to be extended on its own without applying any force. When it is extended all the way the gear continues to rotate in the same direction, causing the belt to be wound the wrong way.
  • Pressing the “Test” button displays the message [MSG:WARN: Magnet not detected on Top Right]
  • If I swap the wires of the bottom right and top right arms in the control board the message now reads [MSG:WARN: Magnet not detected on Bottom Right]. This seems to rule out an error in the board.
  • Swapping the wires in both the control board and arms displays the message [MSG:WARN: Magnet not detected on Top Right] again. This rules out an error in the wiring. It seems to definitely be in the top right arm.

Could this be a sensor issue? I’m fairly sure the magnet is correctly seated and I can see the black gear spinning when extending or retracting the belt.

2

When you press Test what version numbers are displayed? I presume you are running the Maslow 4.1 if you had the z-axis problem.

This points to a problem where either the magnet is not seated properly on top right or there is a fault on the sensor board. There was a problem with some sensor boards where the pins on the board are too long and are shorting out. Trimming them may fix the problem. Unfortunately, it means pulling that arm apart to check both of these.

3

Hi Ian,

Thanks for your prompt response.
I will take the arm apart to check the magnet and sensor board. Which pins would I be looking for?

4

This error message means that the board is able to talk to the encoder chip and the encoder chip is reporting that the magnetic field that it’s sensing is too weak which does point to it being an issue with the magnet.

5

Hi bar

Thanks for chiming in. The magnet is glued in place as per the instructions, do you have any idea how to get it out?
I assume the magnet itself is fine.

1 Like
6

Are you 100% sure that the roller is in place such that the magnet is closest to the chip which detects it?

I would expect the magnet to be OK, but it could be the first bad magnet!

7

The connector pins on the underside of the sensor board. Also check the magnet is in the correct roller and up the right way. It must be near the sensor chip.

1 Like
8

Sure enough the magnet was upside down. What a rookie mistake :frowning:
The dead giveaway was the fact I could see just one magnet when holding the router arm assembly upside down. The other 3 magnets were hidden inside the arms as they are supposed to be since they are on the top.
I just re-assembled and tested it, all works fine now!
Thank you very much for all of your support.

3 Likes
9

Excellent! Good fix!