PID Silvia

Last Sunday, my coffee friend, Irving who is an engineer finally PID his Silvia. This is less than a year after he bought the machine. Below is the unedited outline of his PID adventure.

It was an impulsive purchase. I was walking by an shop selling control & electronics stuff. They have this OMRON E5CZ controller that costs RM200, a fraction of what a new Fuji PXR3 would cost (about RM600). Except for the thermocouple, they have all the stuff I neede to construct the PID modification.

I had to do the mod in a “minimally instrusive” manner, i.e all the mods I do must be 100% reversible, with minimum trace. Which means no drilling, grinding or disfuguring any part of my Silvia, internal or external. Here’s what I’ve done.

1. The thermocouple sensor is mounted to a washer (as shownin Murphy’s Silvia Mod).
2. The solid state relay (SSR) is mounted using an existing screw in the Silvia (I just have to use an M4 sized nut to secure it).
3. I’m using high powered magnets to attach the PID box to the Silvia (no double sided tape).
4. PID controller box can be easity removed/detached – using connectors

The cost?:

1. Omron E5CZ Controller – RM200
2. Solid State Relay 25A – RM35
3. Thermocouple – RM34 (bought from Farnell – www.myfarnell.com)
4. Box for PID controller – RM3.80
5. Lugs cables etc. – RM5
6. Connector (Multipole) – RM3.40
7. Connector (Thermocouple) – RM22
8. Magnets – RM5

Total Cost : RM308.20

Note: the magnet are of 10sen coins size. I’ve used 4 of them. bought them at a stationery shop near my place… strong stuff

I’ve actually spend a bit more money than that, experimenting & testing with a few other ideas. The problem is that 1/32 DIN (25mm x 48mm) controllers are not popular at all in Malaysia. All I could get is the 1/16 DIN ones (48mm x 48mm). 1/32 controllers like the Fuji PXR3 and Omron E5GN would cost about RM500-600 and a lead time of 4 weeks. But with the compact sized controller, you can do a lot of nice stuff (fits well into a lot of common sized boxes).

Another thing… this is a basic brew temperature controller only. I did not put in the Steam temperature control. To do so, I’ll need to add the following :

1. 2 relays ( about RM26 total)
2. An input module for the Omron E5CZ controller (Don’t know how much).

But that’s for the future.

Now Irving is truly a coffee geek now. I will have to drop by Irving’s place and see it in action before I PID my Silvia.

Click here to view Irving’s mod.

If you are interested to know more about PID your coffee machine or what exactly is PID, check out these resources.

• Rancilio PID Kit review by Randy Glass
  
• MLG PID Kit
• A Tail about Silvia
• Murphy’s Silvia PID Page
• The Case of Temperature Surfing & PID Control
• Terry Stockdale’s Silvia PID