All this talk about PIDs in Sydney got to me, and I decided it was time Silvia in Melbourne was taken to the next level.
The thermocouple and digital multimeter I’ve been using took the guesswork out of when to pull shots. But I like the idea of walking up to the machine and making coffee without first checking the temperaturet and making adjustments accordingly with the steam switch (to go higher) or brew switch (to cool).
Why do it?
The idea of the machine having a day-long stable temperature appeals. No wild fluctuations of around 20°, along with the internal pressure stresses that produces.
Also why: “because it’s there”. And because it will be fun to do.
Mission Statement
The project has to be cost effective. I can afford to splash out with the cash, but I don’t want to end up adding 40 per cent to the original cost of the Silvia, either. The PID does not have to be extremely sophisticated with multiple loops, dual output controls etc.
The Journey Begins
First, the obvious: choosing a PID.
I gave up on Ebay because after researching what those hitherto meaningless PID specs mean, the stuff on offer was either short on detail, unsuitable, or used ---plucked from industrial ovens. Many have electro-magnetic mechanical relays which not only go clickety-click, but are rated below the necessary current of at least 5 amps.
One, offered by ColdfusionX Universal, the TET 7100, looked promising. But a Google search showed it got poor reviews and has a one-line display anyway.
Last year I spoke to Ron Fowler, at OneTemp, but the quote was too high at around $200. This time I spoke to their Melbourne office and was quoted $294 for their supposedly “cheapest” controller, a Shimaden. SR91. And $34.20 for a 40-amp relay. Plus GST.
Add a few more dollars for a box, wiring, bracket and terminals and it’s all looking like a ridiculous add-on for a $700 machine.
I was resigned to give up on the whole project when, back at Ebay I came across a very modestly-priced model which had all the features I sought.
To be continued.
-Robusto.
The thermocouple and digital multimeter I’ve been using took the guesswork out of when to pull shots. But I like the idea of walking up to the machine and making coffee without first checking the temperaturet and making adjustments accordingly with the steam switch (to go higher) or brew switch (to cool).
Why do it?
The idea of the machine having a day-long stable temperature appeals. No wild fluctuations of around 20°, along with the internal pressure stresses that produces.
Also why: “because it’s there”. And because it will be fun to do.
Mission Statement
The project has to be cost effective. I can afford to splash out with the cash, but I don’t want to end up adding 40 per cent to the original cost of the Silvia, either. The PID does not have to be extremely sophisticated with multiple loops, dual output controls etc.
The Journey Begins
First, the obvious: choosing a PID.
I gave up on Ebay because after researching what those hitherto meaningless PID specs mean, the stuff on offer was either short on detail, unsuitable, or used ---plucked from industrial ovens. Many have electro-magnetic mechanical relays which not only go clickety-click, but are rated below the necessary current of at least 5 amps.
One, offered by ColdfusionX Universal, the TET 7100, looked promising. But a Google search showed it got poor reviews and has a one-line display anyway.
Last year I spoke to Ron Fowler, at OneTemp, but the quote was too high at around $200. This time I spoke to their Melbourne office and was quoted $294 for their supposedly “cheapest” controller, a Shimaden. SR91. And $34.20 for a 40-amp relay. Plus GST.
Add a few more dollars for a box, wiring, bracket and terminals and it’s all looking like a ridiculous add-on for a $700 machine.
I was resigned to give up on the whole project when, back at Ebay I came across a very modestly-priced model which had all the features I sought.
To be continued.
-Robusto.





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