Project help - fan control using using sql data

Hello,

We are currently working on a tunneling project where we will need to track the on/off state of several trucks in the tunnel in order to do fan control. More trucks with engines on = higher fan speed.

The trucks will be tracked using an RFID system, which stores the data directly to an SQL Server database. The fans will be controllable via an Allen Bradley PLC (not sure which model). We will also require a very basic HMI to show what the fans are doing.

I am a software guy but I am new to the world of PLCs and I'm not quite sure where to start. A few other people at our company have some basic experience with Lookout, so they are pushing that.

Essentially, I need a process that checks the database for new rfid events, does some calculations to determine appropriate fan speed and then tells the PLC what to do. What are my options for making this happen?

Thanks.
Steve

Does your shaft have ENTRY and EXIT lanes? if so when a truck enters you could add the RF id to the database (SQL INSERT IGNORE INTO command) and remove the RF id when the truck exits (SQL DELETE FROM xxxx WHERE rfid=truckid)
then, when an update occurs, do a SQL count* to determine how many trucks are in the tunnel, and post this value to the plc.

Obviously you would need to scale the number of trucks to a suitable fan speed etc

cjd1965 said:

Does your shaft have ENTRY and EXIT lanes? if so when a truck enters you could add the RF id to the database (SQL INSERT IGNORE INTO command) and remove the RF id when the truck exits (SQL DELETE FROM xxxx WHERE rfid=truckid)

Click to expand...

Yes, we will be doing something similar to that. My main question is how to go from having the data in the DB to controlling the PLC.

cjd1965 said:

then, when an update occurs, do a SQL count* to determine how many trucks are in the tunnel, and post this value to the plc.

Click to expand...

Where does this logic go? SCADA/HMI? And will I need OPC server to talk to the DB and PLC?

Thanks.
Steve

Factory PMI is an SQL based HMI
http://www.inductiveautomation.com/products/factorypmi/

Wonderware has built in SQL functions

The least expensive option is probably Infilink with Kep server.
The ODBC Client Driver will connect to the SQL server, and the AB driver will connect to the allen bradley.
The KEP server alone will work with any HMI package though.

I am playing with the Factory PMI/KEPServer demo right now. Seems quite nice and sounds like it will do what I want. A little on the expensive side, but not out of the question.

I've also played around with the ODBC driver for KEPServer. I'm assuming that using this plus whatever HMI will meet my needs? (KEPServer + KEP ODBC Driver + HMI/SCADA)

Thanks.

Seems to me you need to include more than just the trucks. How many people will be in tunnel. What kinds of equipment will there be?

As an alternative I think I would look at controlling by exhausted CO2 concentration. This way you will ensure you have the people emissions covered (exhaled air), trucks (exhaust CO2) and other equipment.

Would have ******t CO2 detector in clean air then one or more in tunnel. Run fan speed proportional to rise above ******t.

As an alternative electric equipment will require less ventilation.
This outfit makes coal mining electric equipment.

http://www.samincoinc.com/

EDIT ******t = A M B I E N T
why that gets censored I have no idea.

Dan Bentler