Bed Auto heating after changing to 24v power supply
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I am building a Dbot for reference.
I just changed out my power supply to a 24v supply. I am still in the middle of the build and just got the firmware configured. After turning the bed on once, it seems that the bed just auto heats every time I turn the power on. The SSR gets hot and the LED does not light up until I give a temp through DWC. If I leave it on, it overheats and just keeps going.
I have looked at the auto tuning documentation but I can't get the printer to stay room temp long enough to run the auto tune.
Not sure what I am doing wrong here. Any thoughts?
Does the bed have to be wired differently for 24v and 12v? (I am just looking at the back of the bed and it looks like 2 = Pos / 3 = Ground for 24v - does this matter?) -
What model of SSR do you have? Perhaps you have the + and - output terminals of the SSR wired the wrong way round?
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SSR-25DD
SSR (1) -> Bed +
SSR (2) -> V +
SSR (3) -> DW Bed VIN
SSR (4) -> DW Bed GND -
SSR25DD is basically no good because of its high voltage drop. It has probably overheated and failed. See the very end of https://duet3d.com/wiki/Connecting_a_bed_heater#Low_voltage_.2812V_or_24V.29_DC_bed_heater for recommendations.
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I did come across that last night and I ordered one of the SSRs you suggested. I think it will be a few days. Thanks for the quick responses.
