pastera
NES Member
I'm pretty certain I know why your unit is off on the temp - I think I swapped the two wire types (Chromel vs Alumel) when I wired the controller to the TC socket on the front. Let me know when yo u can spare it for a couple of days and I'll pick it up and fix it.
The autotune adjusts the four main parameters that tune the control (P, I, D and integrator reset) - it only needs to be done once and should be good for a decent range in lead alloy temps.
If your pot holds temps well and doesn't overshoot badly when adding ingots after an autotune - don't mess with it further. If you want to play around, write down the four values and make 25% changes in ONE variable at a time to see what happens. Don't hesitate to ask me if you have a question on tuning.
If you want to move the controller between processes - write down the tune values for each one and put in the saved values when you attach the controller to a different process (melt pot, toaster oven for coating, heat treat oven, etc). No need to autotune unless you have made a big change in the process (like coating half or twice the weight in bullets) and temps aren't controlled well.
The cycle time is the 'r' setting right after the integrator reset (Ar) - I set it to 2 seconds. If the buzz from the heater bothers you, you can adjust this up but will need to rerun autotune. Going too high will cause temperature overshoot because the controller can't react faster than the cycle time.
I also go into the hidden menu (COD) and turn off the display filtering so you see the actual temperature variations (the filtering hides small variances).
Manual (covers other models so not every setting is available)
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