PWM logics of M307
I was getting error because my bed heated up slower than the expected 1.7°C/s
I tried autotuning but apparantly it failed somewhere during phase 4.
I changed the PWM value to 2 and haven't had the error since but I'd like to know what it actually does.
M307 H0 B1 S2.00
Given that the documentation for M307 says:
Snnn maximum PWM to be used used with this heater on a scale of 0 to 1. Default 1.0.
That S2.00 is likely doing nothing. The default was 1.0 and I'd bet that setting it beyond 1 just sets it to 1. Further, I'd bet that the non-error is because the bed was not totally, completely, cooled to room temp when you experimented further.
I would HIGHLY recommend running an autotune, and putting the resulting parameters in config.g.
Oh, and your question: S being scaled 0 to 1, and called "Max PWM", it looks like it is the maximum duty cycle for PWM on the heater specified.
See "duty cycle" here
@Danal sounds plausible to why the error didn't occur anymore. I'll retry tomorrow with a cold bed and report back.
@Danal I just retried with a cold bed and heated up to 70 without getting the error.
I'm printing now so I'll try again tomorrow after setting it back to 1
@Danal I did yeah, it went to phase 4, was cooling down for a while and later when I checked it had an error in phase 4.
Cool (he he). Keep us posted.