Overheating problem

[Bryce Schroeder]

Apparently the trim pots for current were wrongly set. At near maximum! Not sure how this happened as I did not set them like that... anyway, that is still fixed. Thermometer problem remains at this time. Thank you for any suggestions you can offer.

[Bryce Schroeder]

Now that the trim pot current is properly set (had to put it a bit higher for Z than X and Y), they do not seem to overheat, however, the X axis motor seems to be "always going". Its driver never cools below 35C or so and I can hear it quietly making noise. In fact, none of the drivers seem to completely cool back down, they always stay about 32-38C (warm to the touch but not hot). Is this normal?

Thank you. 

[Bryce Schroeder]

Further update: I have, thus far, determined that it is probably not the thermistors that are bad. They both read about 100kOhm at room temperature and decrease to about 90 kOhm when I warm them with my hand. I made these measurements at the connector that plugs into the T0 and T1 pin headers of the RAMPS shield. Eagerly looking forward to any information about troubleshooting thermistors that you may have, and thanks for enduring my repeated messages.

[Paul Bristow]

Hi Bruce,

try checking the connector that plugs into the RAMPS shield. I had one that moved up when plugged in, leading to an intermittent connection and a reading of 357 degrees.

Cheers,

Paul

On Jan 8, 2013, at 00:46 , Bryce Schroeder <bryce.s...@gmail.com> wrote:

> Apparently the trim pots for current were wrongly set. At near maximum! Not sure how this happened as I did not set them like that... anyway, that is still fixed. Thermometer problem remains at this time. Thank you for any suggestions you can offer.

Paul Bristow
/* Though the problems of the world are increasingly complex, the solutions remain embarrassingly simple */

[Bryce Schroeder]

I will investigate that when I get home - it seems highly plausible, as when I disconnect the sensor the reading is also "357"

Thank you.