Dudes about temperature control
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Hi,
This, more than a doubt, is a curiosity. About temperature control.
In a conventional mode, where the heated bed, is connected directly to the Duet Board, the temperature control (of the bed and the nozzle):
- It's progressive. No?
- That's one of the reasons for calibrating it. No?
As I understand that it works. When you select a temperature, in Dwc, the bed (is where I have the main doubt), receives 100% of the 24v, until it almost reaches the target temperature, and when it is close Duet board, lowers the amount of voltage it sends you, enough for it to arrive and maintain, as stable as possible, the target temperature. That's why I ask if it's progressive.
The other option would be, that when it's close to the target temperature, the Duet Board doesn't send voltage, and goes from 0 to 100% of the voltage, turning the bed on and stopping, to maintain the temperature as close as posible of target temperature.
What option uses?
Nozzle heater the same? (think uses another model for tunning temperarure control)And... When you conect bed heater with a SSR (as my case). Does it work the same? It does not sound to me that the SSR can be progressive, open or closed, they let the 220v pass or they do not let anything pass, I do not know for sure.
Thx
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Temp control is either by turning the heater completely on or off (referred to as bang-bang mode) or by using Pulse Width Modulation where the ratio of on to off is varied (referred to as PID mode).
I use PID mode for all heaters.
Frederick
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@peirof Look up PID control on the internet. Then look up PWM (Pulse Width Modulation). You can use PWM with an SSR - it's just that the PWM frequency needs to match the switching frequency of the SSR (usually around 10Hz).
