PWM frequency for bed heater RRF 3.x
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Looking through the docs there only appears to be mention to be able to set the PWM frequency in the 2.x firmware but there is no mention in the 3.x firmware.
I just finished building a Ratrig V-core 3.1 with a 1500watt 500x500 bed and want to make sure I don't stress out the SSR so I would like to set the PWM frequency.
Is there a setting for this in RRF 3.x?
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@JamesM the Q value of M950
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@jay_s_uk Thank you!
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@JamesM where are you looking? Because it’s stated here: https://docs.duet3d.com/User_manual/Connecting_hardware/Heaters_bed#configuring-a-bed-heater
Edit: hmm, rereading that it’s specific to SSRs, and written like you would read the RRF 2 text first. I’ll add a bit to it.Ian
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@droftarts I was looking under the M307 section in the GCode documentation.
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@JamesM Is the bed heater running on AC (e.g. mains)? If so, stressing out the SSR is of lesser importance - assuming your SSR is zero crossing (best if it is in this case) you need a frequency much lower than the frequency of the power supply, e.g. a tenth of the mains frequency or lower (personally I use 3Hz).
