Has anyone else been thinking about more granular temp control, a Fuji PID to be specific? I am not sure if the electronics in the S1 will allow it, or if there is a thermocouple available. It seems like the integrated electronics would see a seperate temp control as a failure on the machine.
I love the temp control and move between 93 an d 97 with good results, but it seems like the sweet spot is somewher in the middle of the 1 degree celcius steps.
One of has to be an engineer, right? :D
PID the S1
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wgaggl
Thought about it a lot, but never did it.
If you do, my advice is not to use a thermocouple, rather use an RTD. Thermocouples have one weak point: the cold junction at the other end of the wires, which make it variable if your ambient temperature isn't constant. With the RTD you won't have that problem, and once you trying to go more precise than one degree variability, you need to care about these things. PIDing a S1, isn't the same as PIDing a Silvia, since the S1 is much more accurate to begin with. Ideally you would be looking for a Class A RTD probe. I thought about mounting it into the 1/8" hex bolt on top of the brewing boiler. This would allow for a maximum sheath length of 1" into the boiler (otherwise getting to close to the heating element). Let me know if you find that probe. :)
PID controller and SSR is the easy part here.
I thought if you leave the built in probe and set it to a temperature close to the set PID temp, then the S1 electronics wouldn't recognize that it's not in control anymore and not report a malfunction.
Wolfgang
If you do, my advice is not to use a thermocouple, rather use an RTD. Thermocouples have one weak point: the cold junction at the other end of the wires, which make it variable if your ambient temperature isn't constant. With the RTD you won't have that problem, and once you trying to go more precise than one degree variability, you need to care about these things. PIDing a S1, isn't the same as PIDing a Silvia, since the S1 is much more accurate to begin with. Ideally you would be looking for a Class A RTD probe. I thought about mounting it into the 1/8" hex bolt on top of the brewing boiler. This would allow for a maximum sheath length of 1" into the boiler (otherwise getting to close to the heating element). Let me know if you find that probe. :)
PID controller and SSR is the easy part here.
I thought if you leave the built in probe and set it to a temperature close to the set PID temp, then the S1 electronics wouldn't recognize that it's not in control anymore and not report a malfunction.
Wolfgang
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wgaggl
Resistive Temperature Detector. Most machines comes with them. Accurate RTDs are more expensive than thermocouples in general; on the other hand thermocouples have a second junction on the other side of that thermocouple wire, where it's fed back into the measurement instrument. That junction is at the mercy of room temperature, and that's where most of the variability in offset comesfrom with thermocouples. RTDs don't have that problem, they change resistance according to the applied temperature. If you google 'RTD temperature sensor' you'll find more. As mentioned to get good results with RTDs you ideally want a 'Class A' sensor for tight tolerances. They are very stable against any environmental temperature changes.Chas wrote:Wolfgang: What's an RTD? That's a new one on me.
Wolfgang