Alarm trigger for drop temperature

Hi all,

I'd like to have your suggestions or opinions how to develop an alarm in the PLC when the water temperature drop to 5°C in 10 minutes.

What could be the right way to start develop the PLC code?

Thank all in advance

1. Determine the brand and model of your PLC, so you can get copies of the User Programming and Operating manuals.

2. Find what digital Outputs that you have avaialble for the Alarm. What PLC Instructions could you use to trigger the Alarm Output? Could you use a Compare to compare the current analog input Water Temperature to some upper or lower limit? As the temperature starts to drop, could you use a PLC Timer to determine if it drops TO 5 degrees in 10 minutes? If 5 degrees C is the ending temperature, then what is the beginning water temperature?

3. Find what Inputs (analog or digital?) that you have for the Water Temperature.

4. Find out the name of the PLC programming software that you have to write the program.

5. Write the program.

take temperatureinput (TI)wait for 10 seconds
take TI again
if dif TI > 10*5/600 the drop is higher.

Thanks so much Shooter....