So you have a Splinter and you'd like to setup temp control in tubomyevic. Problem is funkyjunk tuned the PID settings for the Tubo heater. I've done a little bit of guess and check tuning with the NFE device monitor and arrived at some PID settings that seem to work pretty well so I thought I'd share.
I'm far from an expert on any of this so much of this builds on things I read in the TC Box Mods Firmware Discussions and Customizing thread, and some discussions with folks in the vaporents Discord. Many thanks to funkyjunky, KeroZen, antispleen and everyone else tinkering with their firmware settings.
NOTE: These settings were tested on a Splinter v1, I would assume the Z would prefer larger P and I values.
To insure your mod is compatible with tubomyevic check the list on the firmware page at lamart.ch. That is also where you'll find the latest binary of tubomyevic. If you have an Evic VTwo Mini or VTC Dual there are also zipped folder downloads there with the Joyetech firmware updater for those mods, otherwise you can use NFE Tools to load the binary onto your mod.
Setting up your Splinter
We'll start by configuring the clicks menu. Press the fire button and + to enter the menu. Use the +/- keys to navigate and fire to select the 'Interface' menu, then the 'Clicks' sub-menu. The fire button cycles through the options for each menu item. Mine are set up like this:
I don't use Cruise much but it's a nice option to have. Edit is used to adjust the max power in Tubo (temp control) mode or switch between Tubo and power modes. Clock toggles the clock on/off on the main screen.
Next we'll look at the 'Vaping' menu (the first option on the main menu). The Timer setting here sets the maximum cruise length in seconds. Tstep, LoTemp, and HiTemp are only used by the Temp Step mode; I won't cover them here. W2Cruise is only used by WarmUp mode which I also won't cover and don't recommend with the Splinter. Ecolvl sets the Eco mode which uses some magic to detect draws during cruise and lower the set temp when a draw is not detected. I have Eco mode off (0) but if you're running long cruises you may want to try level 1 or 2.
Now open the 'Algo' sub-menu (Vaping > Algo). This is where the PID magic is configured. Here are my settings (for the numerical settings press fire to select, +/- to adjust then fire again to save):
[Optional] Back out to the 'Vaping' menu and open the 'Modes' sub-menu. Here you can turn off ('N') everything except TCR and POWER. You could also turn off POWER if you only intend to use Tubo mode. Or not. Whatever. This only affects the modes available to you when you click into edit mode.
Next we'll lock our resistance and set the TCR value. From the main menu navigate to Coils > Manage. The Tubo setting should read your Splinter's current resistance. If not try navigating to the Tubo setting and holding fire for two seconds.
Here comes the fuzzy part. This type of temp control is not very accurate since it depends on the locked room temp coil resistance and a TCR coefficient of an unknown alloy. Users report needing to reduce their locked coil resistance by 0.004-0.012 from the 'actual' cold resistance to get their Splinters to put out a temp that seems accurate to the temp shown on the mod. I'm using a lower TCR than many people so my change in locked resistance is on the low end. Right now my Splinter v1 reads 0.279, rolling that down 0.004 to 0.275 seems to put me in the right ballpark. Make sure the lock icon appears next to the resistance (if it does not selecting the resistance setting again and pressing fire should toggle the lock on). Set Check to 'No'. Here I stored my 'actual' cold resistance in the S/S slot just as a memory aide:
Setting TCR: Navigate to Coils > TUBO Set. Set M1, M2, and M3 to 145:
As I mentioned above, my TCR setting is on the low end. If you feel your device is running hot or cool I recommend tuning by changing your locked resistance. You could also try adjusting the TCR but you should probably chose one to adjust and stick with it.
My main screen now looks like this:
To change between modes (eg. if you'd like to switch to power mode) click into edit mode (Edit on the clicks menu, so if you're following along with me that's three clicks) and using + to cycle between modes. Also in edit mode: you can navigate to the other lines on the main screen with the - button and use the + button to cycle through display options or start adjusting the maximum power output.
What max power output should you use?
The PID settings will keep the heater from over-heating so it depends on the batteries and how many are in your mod. Stealing a recommendation from Mooch:
- 10A rating = 30W / battery
- 15A rating = 45W / battery
- 20A rating = 60W / battery
- 25A rating = 75W / battery
That's it, you should hopefully be pretty close to dialed in (though I recommend starting at 360-380F instead of 400F just to be safe). The rest of this will discuss some optional additional tuning stuff and how to get the NFETools Device Monitor working.
Advanced Setup (Optional)
For the most part you should leave the 'Expert' menu alone. The BAT setting can be used to specify the battery model you're using. This will make the battery gauge more accurate and limit the max amperage drawn based on CDR.
I set up the PID values to be responsive without being super aggressive. They give a slight overshoot if you're not drawing so they're pretty spot on if you start drawing shortly before it hits the set temp. I started testing at 500, 80, 10 and went as high as 750, 600, 10 which was still pretty good but overshot more. I tried testing dry and through water so I could draw pretty hard and it seemed to still keep up well at the settings I landed on.
What do the PID values actually mean?
P is the proportional term in mW/ºC. Proportional, in our case, to the desired change in temperature. If you start at room temperature (around 20ºC) and try to fire to 180ºC you're looking at a desired change of around 160ºC. So, P=750 gives you 3/4 of a watt per ºC or 120W. So unless you're using a multi-battery mod that's already going to be throttled by the maximum wattage setting until it gets closer to the set temp but that will only take fractions of a second.
I is the integral term. Its effect is proportional to the sum of the difference from the set temp over time. It's given in mW/°C/s.
D is the derivative term. Its effect is proportional to the rate of change in the difference between actual temp and set temp. It's given in mW.s/°C
To get NFE Device Monitor working:
on the 'Expert' menu set USB to COM and NFE to ON. I also couldn't get it working with the most recent builds of NFE Tools had to download this outdated version.