3.5 KiB
Basic tests
We test the behaviour, times and temperature of 3 cartridge heaters on a sheetpress.
Setup
- 3 Cartridge heaters at 220V
- Room temperature : 33 degc
- Stronger air circulation in the workshop
- PID : Inkbird - 100VH
- Cartridge heater : 12mm OD / 8cm L
- Extra probe to PID probe difference around 15 degc (at 220degc)
- Addtional probe to measure frame and wool temperatures
- Press Plate : EN AW 5083 [AlMg4,5Mn0,7], 10mm
- Insulation wol: RockWool - ProRox WM960
Results
- PID Probe to extra probe difference : 10-25%
- Autotuning duration for 50 degC : 18 mins
- Temperature loss from heated to unheated cell (33cm) : ~30 - 50%
Speeds
Times to raise temperature, 220degc
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at 130C, it took 17 secs to increase by one degc | Outer temperture (wool) : room temp
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at 140C, it took 28 secs to increase by one degc | Outer temperture : room temp
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at 155C, it took 38 secs to increase by one degc | Outer temperture : room temp | Frame-temperature : 50degc
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at 160C, it took 41 secs to increase by one degc | Outer temperture : room temp | Frame-temperature : 52degc
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at 170C, it took 52 secs to increase by one degc | Outer temperture : room temp | Frame-temperature : 53degc
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at 180C, it took 58 secs to increase by one degc | Outer temperture : room temp | Frame-temperature : 53degc
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at 190C, it took 1:54 mins to increase by one degc | Outer temperture : room temp | Frame-temperature : 53degc
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at 200C, it took 1:55 mins to increase by one degc | Outer temperture : 34 degc | Frame-temperature : 68degc
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at 210C, it took 3:02 mins to increase by one degc | Outer temperture : 35 degc | Frame-temperature : 82degc
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at 220C, it took 12:05 mins to increase by one degc | Outer temperture : 36 degc | Frame-temperature : 84degc
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after 220C, it takes 12:05 - 18 mins to increase by one degc | Outer temperture : 36 degc | Frame-temperature : 84degc
Total : Time to heat from 33 degC to 210degc: 2:15 h::mm
Total : Time to heat from 33 degC to 220degc: 3:28 h::mm
Times to increase temperature (turn off heating)
- at 214degc (at the PID probe), it took 0:17 secs to cool down by 1 degc !
- at 205degc (at the extra probe - on the heater block), it took 0:21 secs to cool down by 1 degc !
Conclusions
- research: we need better probes and some better logging
- build: PID probe should penetrate the heat plate
- build: Heat plate should be thicker
- build: Cartridge heater blocks should be bigger
- times: After, 200 degc (at 33 degc room temp), the system has a really hard time to increase temperature at all, especially strong wind/air circulation at the perimeter affects this times significantly
- performance: it's unlikely to go beyond 220/230 degc, especially in colder environments
- see more remarks from the network
- serial partition heating: with a window of 18 secs to cool down one degc (heater off), we might have still a chance with better heat containment as recommended in the build remarks