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Had a weird issue last night when I tried out repetier host again. I set my bed temp to 90c and started a 5hr print. After about an hour and a half I went to check on it to make sure everything was ok when I notice my bed temp was way too hot. Bed temp was set at 90c but it for some reason climbed up to 117c and held that for at least an hour. When I caught it I drop the temp down in manual control by 2c and it fell down to 90c where it stayed for the rest of the print.

Any ideas what could have caused this?

My print basically fused with the blue painters tape and was really tough to remove, no bed adhesion issue there lol

You must have the newer PSU...

What slicer did you use? If you open the G-code in a text editor, do you find any M140 or M190 commands other than the one at the beginning and the one at the end?

I was using slicer at the time, Im going to be doing another print here in a few mins and see if I get the same issue or if it was just a fluke.

It's unclear how you knew the temperature was 117C, the host just sends a request for the temperature.
If the LCD was saying something like 117/90, there is something very wrong, it's possible with bad PID settings for the bed for it to oscillate that much, but the bed heater should be off at that point, if it wasn't, I'd suspect a bad Mosfet on the RAMBO and if it is bad you want to watch it.
If the LCD was saying 90/90 and you got the 117C from an external thermometer, then it's an issue with the thermistor calibration or placement.
If the LCD read 117/117 or similar then something sent a gcode to change the temperature, one thing to watch in repetier host is the Start and End GCode tabs, they get run before the actual GCode starts and Ends, make sure they are clear and saved.

Polygonhell wrote:It's unclear how you knew the temperature was 117C, the host just sends a request for the temperature.
If the LCD was saying something like 117/90, there is something very wrong, it's possible with bad PID settings for the bed for it to oscillate that much, but the bed heater should be off at that point, if it wasn't, I'd suspect a bad Mosfet on the RAMBO and if it is bad you want to watch it.
If the LCD was saying 90/90 and you got the 117C from an external thermometer, then it's an issue with the thermistor calibration or placement.
If the LCD read 117/117 or similar then something sent a gcode to change the temperature, one thing to watch in repetier host is the Start and End GCode tabs, they get run before the actual GCode starts and Ends, make sure they are clear and saved.

The lcd screen said 117 target 90 and repetier host said that it was 117 with a target of 90. This is the first and only time that has ever happened. ive done a few prints since and havent had an issue yet. I did set the temp to 60 manually on the printer to do a rezero my z then i set the temp to 90 in rep host, could that possibly have anything to do with it?