After a few days of thinking about it, to me it looks like the following would be a very luxurious solution for controlling the temperature of reactions (money shall not be the matter, emphasis is on quality/ease of use) :
A heating mantle connected to a PID temperature controller that has the sensor (PTFE) directly inside the reaction medium. This works in the range from 0 - 250 °C, no messing around with bath fluids, easy to cool rxn down with water bath which can quickly replace the heating mantle, very accurate measurements - sensor in rxn medium eliminates the need to control 2 temperatures, the one of the bath and the one of the flask contents, the error is 1 K at 150 °C and 1.5 K at 250°C.
Despite the hefty price of such a setup, including the need to buy multiple heating mantles for varying flask sizes, do you think it has obvious disatvantages that might not have crossed my mind yet ??
You will have a lot of fun (read headaches) programming the PID as they must be tuned to each particular situation. Make sure the Proportional is not "bang bang"(all on /all off) type but rather some type of Phase control or PWM.
My guess is that after the novelty wears off it will stay on "manual" most of the time.
On a positive note a PID controller properly set up is very useful for repetitive reactions that will require much less monitoring and provide much more sleep.
So then what's the magic behind products like the IKA ETS-D 4 ?
I think it's nothing but a PID controller including some software to optimise the P,I and D values.
Electronic contact thermometer with fuzzy logic control and RESET function, incl. sensor H 62. For IKAMAGŪ magnetic stirrers and IKATHERMŪ heating plates with contact thermometer bushing according to DIN 12878. Ensures perfect temperature control without overshooting the set temperature, even in the case of quick heating.
Patented: 3 modes of operation guarantee optimum adjustment to your working method.
Operating mode A:
Suitable for work with varying parameters (from -10 °C to 400 °C).
Safety temperature adjustable.
Operating mode B:
Suitable for series operation under uniform conditions
Operating mode C:
Suitable for unsupervised operation. All values are taken from the memory. This ensures perfect protection against inadvertent or improper adjustment.
........Operating mode C:
Suitable for unsupervised operation. All values are taken from the memory. This ensures perfect protection against inadvertent or improper adjustment............
If you will need only temp control with limit protection then a simple RTD, thermistor or thermocouple type control will do this. Some will accept all three types of sensors. Check Omega.
It's the "C mode" that a PID is intended for and the programing of the Integral and Derivative into the memory take some experimentation. These newer "fuzzy" logic
types with preprogramed heating sequences claim to do it all for you but I have serious doubts about trusting this for a critical reaction unless of course you have verified it.
If you can afford the IKA then get it as it has the more or less "manual" mode A also.
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