This question is regarding a 3D printer, specifically its heat bed. The head bed is a PCB heater with a resistance of 0.9 Ohms, so it's drawing around 13 Amps when supplied with 12 Volts.
I recently switched from Bang-Bang to PID controlled bed heating. The stock firmware pulsed On/Off with about 5 seconds each cycle. Now with PID, my bed keeps its temperature much more stable, the frequency is around 7Hz.
Although the total amount of energy used for heating should be less now since the heating is more efficient and doesn't waste energy by cooling down, I am a bit concerned of the fast pulsing of the rather high amperage.
So I was wondering, do the faster cycles cause more stress on the components (I am thinking MOSFET on the board and components inside the PSU) or is this negligible? I am particularly curious since this is a rather low budget printer (Anycubic i3 Mega, $350 printer with a generic unbranded PSU) and I don't want to push its limits too much. I suppose the power supply is a switching mode one. Are those safe to pulse like this at fairly high amps? The PSU is rated for 25A.
The only thing I can observe is a very faint noise with the same frequency as the pulses. Might have been the same on 5 second cycles, I was just not paying attention to it back then.
I'd be very glad if somebody could chime in on this.
Thanks in advance.