elec4fun
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Hi everybody,
I need to design a system controlling the temperature in a 3U rack. The temperature inside the rack must follows the outside temperature +/- 7°C. In the rack it'll have a fans and a heater.
The problem is: How am I going to control the fan ANd the heater with one PID ? I have some ideas...
- I could have a multiplexer. When the PID output is positive the heater is on and fan is off. When the PID output is negative heater off and fan on.
- I could have the fan and the heater coupled. When PID output is 50% both work at 50%. When PID output decreases heater level decreases and fan level increses...
What do you think of these ideas ? Do you have others ones ?
In both case, how can I determinate PID coef ? I know Ziegler Nichols is a good method but here how can I use this method ? I think this problem hs something to do with SIMO systems (Single Input, Multiple Output) but I couldn't find any documentation on it....
Regards,
Franck.
I need to design a system controlling the temperature in a 3U rack. The temperature inside the rack must follows the outside temperature +/- 7°C. In the rack it'll have a fans and a heater.
The problem is: How am I going to control the fan ANd the heater with one PID ? I have some ideas...
- I could have a multiplexer. When the PID output is positive the heater is on and fan is off. When the PID output is negative heater off and fan on.
- I could have the fan and the heater coupled. When PID output is 50% both work at 50%. When PID output decreases heater level decreases and fan level increses...
What do you think of these ideas ? Do you have others ones ?
In both case, how can I determinate PID coef ? I know Ziegler Nichols is a good method but here how can I use this method ? I think this problem hs something to do with SIMO systems (Single Input, Multiple Output) but I couldn't find any documentation on it....
Regards,
Franck.