#garfield Logs

Jun 18 2025

02:25 AM * rifraf looks for some inline fuse holders
03:29 AM rifraf: ok we are safe, 10A trippable powerboard, into watt meter, then 15A fuse on line in, drawing 4.4 watts
03:30 AM rifraf: the controller does not have an on button, guess i need to turn timer on on mode next
03:35 AM rifraf: timer always on without jumpers in it, has manual on/off, jumpers work, need a knob on the only pot
03:59 AM rifraf: ok we had lift off for a few seconds, drawing 4400w, 20A, so obviously tripped the powerboard after a few seconds
04:00 AM rifraf: which is good and bad, i didn't think 10A would be enough, time to see if i have a high amp outlet, remove a few coils for testing
04:01 AM rifraf: maybe i wire them in series for a start?
04:01 AM rifraf: anyone awake?
04:08 AM rifraf: bypassed powerboard, worked for 30 seconds, blew 15A fuse
04:08 AM rifraf: going to 20A, the door was warm inside :)
04:13 AM rifraf: simmerstat running for about 20 seconds at a time them clicking off, but goes back on after a bit
04:16 AM rifraf: stays on if i turn the knob, this thing worksm at 25C
04:19 AM rifraf: how handy that i just got a thermal camara last month
04:19 AM rifraf: 20A fuse cooked :(
04:20 AM rifraf: maybe thats why they don't have fuses
04:22 AM rifraf: ok the door much hotter inside that the walls, 3 sides and roof at about 100C, but door at 160C
04:24 AM rifraf: need to wire for 10A i think, with 15amp fuse, all cable getting pretty warm
04:24 AM rifraf: photos coming
04:27 AM rifraf: https://desire3d.com/images/public/kiln/insideheat.bmp
04:28 AM rifraf: https://desire3d.com/images/public/kiln/door-insideheat.bmp
04:29 AM rifraf: hoe exciting :)
04:29 AM rifraf: and you are all just sleeping
04:32 AM rifraf: https://desire3d.com/images/public/kiln/contactor.jpg
04:33 AM rifraf: door is on T1 and 14, must be less resistance, 2 other wires must run 2 walls, and last 2 run a wall and roof
04:37 AM rifraf: disconnect all coils and measure resistance? or wire them all in series for now to limit current fully?
04:55 AM Tom_L: aandrew, my diagram has CS0 on 24 and CS1 on 26 (they're calling it chip enable). is that correct?
04:56 AM Tom_L: i think the last time i got this working it was under rasbpi's own os not debian 12 and this may be the difference
05:08 AM Tom_L: and the rpi4 spi isn't working either under debian12
05:08 AM Tom_L: i'm betting that's the difference
06:59 AM rue_mohr: rifraf,
06:59 AM rue_mohr: the control needs fuses
06:59 AM rue_mohr: as I said
06:59 AM rue_mohr: put 1A fuses off the red and yellow lines from the contactor to the controls
07:00 AM rue_mohr: incomming doesn't matter, its protected from your panel breaker
07:00 AM rue_mohr: BUT PUT 1A FUSES TO THE POWER OF THE CONTROLS
07:01 AM rue_mohr: BUT PUT 1A FUSES TO THE POWER OF THE CONTROLS
07:01 AM rue_mohr: BUT PUT 1A FUSES TO THE POWER OF THE CONTROLS
07:01 AM rue_mohr: BUT PUT 1A FUSES TO THE POWER OF THE CONTROLS
07:01 AM rue_mohr: BUT PUT 1A FUSES TO THE POWER OF THE CONTROLS
07:01 AM rue_mohr: BUT PUT 1A FUSES TO THE POWER OF THE CONTROLS
07:01 AM rue_mohr: BUT PUT 1A FUSES TO THE POWER OF THE CONTROLS
07:01 AM rue_mohr: BUT PUT 1A FUSES TO THE POWER OF THE CONTROLS
07:01 AM rue_mohr: BUT PUT 1A FUSES TO THE POWER OF THE CONTROLS
07:01 AM rue_mohr: BUT PUT 1A FUSES TO THE POWER OF THE CONTROLS
07:01 AM rue_mohr: BUT PUT 1A FUSES TO THE POWER OF THE CONTROLS
07:02 AM rue_mohr: rifraf, the reason is that if your kiln is on a 20A circuit and one of those tiny little control lines shorts, all that tiny wiring will burn up
07:02 AM rue_mohr: BUT PUT 1A FUSES TO THE POWER OF THE CONTROLS
07:02 AM rue_mohr: so that the wires of the controls dont catch fire if something shorts
07:41 AM rifraf: ho ruie, i am getting roasted in ##electronics, glad you woke up
07:41 AM rifraf: yes i know, i have a few 3A fuses left, have killed most of the 15A and 20A already
07:42 AM rifraf: rue, so i have heat, all coils in series = 2.2Amp draw, hard to get past 100C though
07:42 AM Tom_L: what's tin foil rated for?
07:43 AM rifraf: at least 10A if you double it up
07:44 AM rifraf: with the 2 oven coils in paralell and then the door coild added in series 4A draw
07:44 AM rifraf: all in paralell 20A draw
07:44 AM rifraf: i need the sweet 10A spot
07:45 AM rifraf: i think i am going to go measure each coild again now, the door always hotter than the oven walls and roof
07:46 AM rifraf: https://desire3d.com/images/public/kiln/oven1.jpg https://desire3d.com/images/public/kiln/oven2.jpg
07:48 AM rifraf: how cool is thermal camera, better than using fingers to feel the difference :)
07:49 AM Tom_L: so impersonal though
08:08 AM rifraf: ok got proper coils readings for all 3 with the new meter, oven coil 1 = 30.57 ohm, oven coil 2 - 30.22 ohm, door coil - 44.71 ohm
08:10 AM rifraf: all in series drew 2.22A with 240V, calc says 2.27 so all good there
08:11 AM rifraf: with 2 x oven coils in paralell and then the door in series drew 4A
08:11 AM rifraf: calc say 4.06A so all goo there
08:11 AM rifraf: all in parallel draws 20A
08:12 AM rifraf: how to get the 10A range or a bit less?
08:12 AM rifraf: don't worry no more physical test tonight, just theory
08:16 AM rifraf: calc says all in paralell about 21A
08:16 AM rifraf: so things are adding up ok
08:18 AM rifraf: appears that i really need a 20A outlet, or run without the door for now would be 15A in paralell for the 2 oven coils
09:26 AM rifraf: no one has the 10A solution yet?
09:27 AM rifraf: 2 oven coils coils in series, then paralell that with the door coil, should be about 9.2A
09:27 AM rifraf: gonna try tomorrow, to much tequila lost tonight
09:28 AM rifraf: rue_mohr where did you run off to after your fuse comments, i will add the 1 amp fuse tomorrow don't worry
09:54 AM aandrew: Tom_L: could be; Just use whatever gpio works for you. I think I used 21 just to match some board I was cloning
10:36 AM Tom_L: the point being, that's how you go about assigning pins..
12:53 PM aandrew: yes that is how you assign pins (as far as I am aware anyway)
06:07 PM rue_mohr: the controls should have about a 1A fuse
06:07 PM rue_mohr: do this where the red and yellow wire come off the power contactor