| ??? 01/10/05 16:05 Read: times |
#84678 - Step respons Responding to: ???'s previous message |
Hello Steve
I had similar problem with drying presure air. I should get 0°C to 4°C with Peltier elements of 1kW and if komressor was not working no powerconsumtion was allowed. I did solv it by overriding the PID during startup because at startup i had 20°C and had to cool down as fast as I could while the komressor was producing hot air. And only when I reached the 4°C I switched over to PID. This took about 30 seconds. Did this in 1997 have no problem with it. But you need enough spare cooling power to be fast. The real needed power when the kompressor was running was only about 250W. This were 20 Peltier modules 50W paralel working each mounted on 0,5°K/W heat sink and ventilated with a fan. So I suggest that the kind of strategy for control is not the main question. Did you check the cooling at full power of the module? How many dergrees per second can you sink the temperature with your element? Is it really enough to solve the problem? On the other hand 0.05°C tolerance is very littel and Peltier elemends have some seconds respons time. So I think at setpoint PID is recomendet. Peter |
| Topic | Author | Date |
| OT Step responses | 01/01/70 00:00 | |
| Step respons | 01/01/70 00:00 | |
| Happy with PID | 01/01/70 00:00 | |
| Re Happy with PID | 01/01/70 00:00 | |
| more details | 01/01/70 00:00 | |
| Making Use of Three Sensors | 01/01/70 00:00 | |
| Heat pipe? | 01/01/70 00:00 | |
| Minimizing Settling Time | 01/01/70 00:00 | |
| Timing | 01/01/70 00:00 | |
| Heat Transfer Rates and Efficiency | 01/01/70 00:00 | |
| Nice estimation | 01/01/70 00:00 | |
| Worked that out | 01/01/70 00:00 | |
| Segments of different PID parameters | 01/01/70 00:00 | |
| integrating cap | 01/01/70 00:00 | |
| Abruptly changing... | 01/01/70 00:00 | |
| Exaclty | 01/01/70 00:00 | |
| Have you Read Above? | 01/01/70 00:00 | |
| Sorry | 01/01/70 00:00 | |
| Maybe this can help? | 01/01/70 00:00 | |
| Interesting | 01/01/70 00:00 | |
| Reference | 01/01/70 00:00 | |
RE: Reference | 01/01/70 00:00 |