tips needed.

Dears,

I am going to do a program on ventilation system,where a CO2 sensor will sense the level of CO2,based on that the speed of the fans and also the no. of fans to be operate will be controlled.and all of them will be done by a centrally located PLC.and it commands the MCC panels in different zones . its actually a CAR PARKING AREA.

I need to know how the out put of the sensor is to be sampled? I am a beginner in this field.

Subho1041 said:

I need to know how the out put of the sensor is to be sampled? I am a beginner in this field.

Click to expand...

This was a really hard nut, but I think maybe I would have started with getting tech info about the sensor.



Kalle

Subho1041 said:

Dears,

I am going to do a program on ventilation system,where a CO2 sensor will sense the level of CO2,based on that the speed of the fans and also the no. of fans to be operate will be controlled.and all of them will be done by a centrally located PLC.and it commands the MCC panels in different zones . its actually a CAR PARKING AREA. I need to know how the out put of the sensor is to be sampled? I am a beginner in this field.

Click to expand...

I think I would also consider carbon monoxide and if you have smoke and or heat sensors consider (fire suppression system) tying it and ventilation control together. More than likely you will want to shut down ventilation in fire THEN restart when OK to do so. IF you do this consult with your fire dept and get ready to buy some NFPA publications.

Instrument wise my first stop would be
http://www.vaisala.com/en/Pages/default.aspx

Dan Bentler

vaisala indeed is a good one for this. use it a lot as OEM have 4/20 mA output.
I even use a valve station to have only one sensor in the cabinet and some hoses to the several compartments. with a small pump and a suction detection (from a washing machine principle).
Then i have two loops, one for control it switches every 2 minutes (my hoses are 100 meter long at 1m/s) and if level too high it switches on a stage of ventilation, etc, if low enough it switches down.
the other is alarm, when way too high, alarm sounds and all fans run like hell to evacuate people, in my case i can stop fans to damp fire but it must be done by manual in your case i have manned unmanned keyswitch as it are holds on a big reefer ship.