PID and Variable Relay

[gr3]

Why would you not want your PIN hooked to be able to control element voltage and temp. I'm wondering if a manual control relay in line would be a good thing.

 

[doug293cz]

I don't think anyone can understand your question. Try giving a more detailed explanation of what you are trying to do.

Brew on

 

[ajdelange]

Probably the best answer is that we do in fact control the voltage applied to the element by turning it on and off. This is not the instantaneous voltage but rather the rms voltage. Applying 220 V at a 50% duty cycle is applying an rms voltage of 220/sqrt(2), for example.

We are concerned with controlling the temperature of the load (the mash), not the temperature of the heat source except broadly in that we don't want it to go to such a high temperature that scorching can occur.

 

[Bobby_M]

Except that there is a reasonable use for PWM coupled with PID (at the same time) if you want to have a maximum wattage element that can be forced to perform at a lower wattage no matter what the PID is trying to do. In the case of a recirculating BIAB or a RIMS, you don't ever want a PID trying to run full 5500 watts (at least I don't). I've been made aware that many PIDs do in fact have a max output setting buried in the menus but not something that is set on the fly.