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Topic: Silvia PID TET 7100 (2 msgs / 76 lines)
1) From: Dan May
This goes out to Mike Chester who successfully installed a TET 7100.  I als=
o
purchased the TET 7100.  However, I was not successful in autotuning.  Woul=
d
you mind recounting your step by step setup of the PID.  As you know, the
online directions leave something to be desired.  Thanks.  Dan

2) From: Mike Chester
This is a multi-part message in MIME format.
Dan,
I am not sure what you have tried so far so I will start at the =
beginning.  I don't mean to insult you by stating the obvious. I'm just =
trying to be complete.  
First, I assume that al of the wiring is correct. The polarity on the TC =
and on the output to the SSR are important.  (On my TC, the red wire =
needed to be connected to the - terminal.  This is the opposite of most =
color coding.)
Start with a cool Sylvia.  Turn on the power to the PID and Sylvia.  The =
output (boiler element) should be off at this point.
Press SET to enter setup mode. 
The > key selects what parameter you are setting and the up and down =
arrow keys make the adjustments.  I set up the parameters as follows:
Inty (temp sensor)  Set to type of thermocouple you are using.  I used a =
K, but yours may vary.
Outy (Type of output)  Set to 2 for SSR
Caty (PID algorithm)  I initially set this for fuzzy logic (2) but the =
results were flaky.  I set it normal,fast acting (0) and it works =
properly.
pSb  (error correct)  I left this at 0 which gives me the temp readout =
at to top of the boiler where the TC is attached.  Later, if you want =
this can be adjusted with an offset so that the display shows a =
temperature closer to that at the brew group.  
Rd (heating / cooling) Set to 0 for heating
CorF (Celsius or Fahrenheit)  Set to 1 for F, 0 for C.
End (exits setup)
Press the up and down arrow keys to set the target temperature.  I used =
228 on mine.  This should give you about 205 water at the group head.  =
You may need to fine tune this adjustment later for your particular =
machine.  
To start the auto-tuning, press and hold the > key until the AT light =
begins to blink.  During the AT cycle the heater in Sylvia should cycle =
on and it will overshoot the target temp.  It will turn off and drop =
below and try a different ramp to temp.  It will keep cycling until it =
"learns" the characteristics of your setup and when it feels it is close =
enough, the AT light should stop blinking, and the temperature should be =
where you have it set.  In operation, the AT light will be on when the =
PID is supposed to be turning on the heater, so the heater light on =
Sylvia should also be on.  It will blink on and off a lot when you are =
near the correct temperature, to prevent overshooting or undershooting =
the set temperature. 
There are a lot of other adjustments that you can make from the manual =
that I sent to you off list, but I would not fool with them.  
I hope that this helps.  Write again if you need any further assistance.
Mike Chester


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