Re: Heads compression - how do you compress yours?
Treat the 2/3 section as your main column from the design point of view with the short section as an add in for when you want neutral. I wouldn't bother fitting any temp sensors in the short section.
In the longer section it is up to you where you place sensors but I find it convenient to have 1 main sensor (somewhere) in the head itself, and a supplementary sensor about 1/3 of the column length down from the head. Just for a bit of advanced warning of temp changes.
I use a 2 channel temp sensor that reads out both temperatures at the same time (or the differential between them) which I find convenient.
Where you put the sensor in the head is just a matter of convenience, but it helps if it is above the reflux return, so that it is only exposed to product vapour.
In the longer section it is up to you where you place sensors but I find it convenient to have 1 main sensor (somewhere) in the head itself, and a supplementary sensor about 1/3 of the column length down from the head. Just for a bit of advanced warning of temp changes.
I use a 2 channel temp sensor that reads out both temperatures at the same time (or the differential between them) which I find convenient.
Where you put the sensor in the head is just a matter of convenience, but it helps if it is above the reflux return, so that it is only exposed to product vapour.

roll on Aug.