12/08/23
Baking testing. Aim to find relationship between heater temperature setpoint and the temperature of the chamber and floating temperature in the baking volume. Behaviour of the heater tempertures and ability to control the heating is also required. Ambient chamber temperature ~22 C. Interaction chamber temperatures will be raised to the level of the CARME chamber throughout, starting temperature of the interaction chamber with heating off is 28 C. P = 7.5e-9 mbar
CARME thermocouple temperatures can be read from the monitoring code which is currently running in a screen session on the baking pi. Heater temperatures and pressure in YR09 can be read from Grafana.
15:40 CARME heaters turned on, set point 50 C. Ramping is ~ 1C per minute for the heaters.
16:00 Thermocouples inside baking volume show small increases. Setpoint increased to 60 C.
16:10 Setpoint increased to 80 C.
16:30 Setpoint increased to 100 C.
16:45 Setpoint increased to 120 C
17:00 Setpoint raised to 150 C. Average chamber temp ~ 25.2 C, bottom of the chamber is ~28C.
17:45 Setpoint was maintained at 150 C, temperatures of the heaters continued to rise past this setpoint and were floating about 200-230 C with large variations in the temperature. At lower setpoints the heater temperature appeared to rise linearly with the 1 C per minute. I do not believe I currently have control of the heating. Average chamber temp 28.8 C with bottom of the chamber ~35-37 C. Heating has been turned off while I grab some food. P = 1e-8 mbar
Next test will be to try and maintain a consistent heater tempreture for a longer period of time, probabably at a lower set temperture.
13/08/23
10:00 Heater setpoint to 50 C. Will maintain at this level for a while to look at increase in chamber temps and see if heater temp remains stable. P = 8.52e-9 mbar
11:47 Heater temperatures have been constant at ~ 55 C for the last hour. Little heating observed in the chamber, requires much larger temperature to heat the baking volume. Setpoint increased to 100 C.
13:10 Heater temperatures have been constant at ~103 C for the last 40 mins or so and appears stable. Temperatures are rising at a steady rate but temps are still low. Interaction chamber heating jackets activated to be a same temperature as CARME. Will require higher temperatures to heat the baking volume.
16:15 Heater temperaturtes have remained constant at ~103 C. Temps inside the baking volume remain low, Increasing heater temperature to 135 C.
18:30 Heaters temperatures remain stable. Larger fluctations are apparent than at a setpoint of 100C with temps between 140 and 150 C. Chamber temperatures increasing avg is ~ 35C, was aiming for 50C over the weekend. Increasing setpoints to 170 C.
20:50 Heater tempretures are stable. Average chamber temp is ~ 40 C. Interaction chamber heaters set to 40 C to keep constant with CARME. Pressure has increased to 2.9e-8 mbar. Heater power outputs are visible in last image, heaters currently turn on at ~80% max power about twice every 5 mins. I expect temps of 250-300 C are required to obtain significant temp increase up to 100 C on the chamber. Chamber temps appear to be fairly stable at this point, will leave for now and check back in a few hours.
23:00 Heater setpoint temp reduced to 135 C to maintain temperatures inside the baking volume overnight with no increase. Heater power has now reduced to < 50 % full power when the eaters are on. Pressure in the chamber is 4.4e-8 mbar.
I believe I now understand the heating system and plan to increase the chamber temperature throughout the day tomorrow. Aim is to get close to full bakeout temperatures. |